&EPA 

United States 

Environmental Protection 

Agency 

Office of Water EPA-44015-90-004 

Regulations and Standards (WH-585) April 1990 

Washington, DC 20460 

Biological Criteria 

National Program Guidance 

For Surface Waters 

Biological Criteria 

National Program Guidance for 

Surf ace Waters 

Criteria and Standards Division 

Office of Water Regulations and Standards 

U. S. Environmental Protection Agency 

401 M Street S.W. 

Washington D. C. 20460 
Contents 

Acknowledgments 

Dedication 

Definitions 

Executive Summary 

Part I: Program Elements 

1. Introduction . . . 

Value of Biological Criteria 

Process for Implementation 

Independent Application of Biological Criteria 

How to Use This Document 

2. Legal Authority 

Section 303 

Section304 

Potential Applications Under the Act 

Potential Applications Under Other Legislation 

3. The Conceptual Framework . 

Premise for Biological Criteria 

Biological Integrity 

Biological Criteria 

Narrative Criteria 

Numeric Criteria 

Refining Aquatic Life Use Classifications 

Developing and Implementing Biological Criteria 

ii 

iv 

iv 

.v 

. vii 

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4 

6 

7 

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9 

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17 

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4. Integrating Biological Criteria in Surface Water Management 

Implementing Biological Criteria . . 

Biological Criteria in State Programs 

Future Directions . . . . . . . . . 

Part II: The Implementation Process 

5. 

6. 

7. 

The Reference Condition . . . . . . . . 

Site-specific Reference Condition . . . . . . . . . 

The Upstream-Downstream Reference Condition 

The Near Field-Far Field Reference Condition 

The Regional Reference Condition 

Paired Watershed Reference Condition 

Ecoregional Reference Condition 

The Biological Survey 

Selecting Aquatic Community Components 

Biological Survey Design 

Selecting the Metric 

Sampling Design 

Hypothesis Testing: Biological Criteria and the Scientific Method 

Hypothesis Testing 

Diagnosis 

References 

Appendix A: Common Questions and Their Answers 

Appendix B: Table of Contents; Biological Criteria-Technical Reference Guide 

Appendix C: Table of Contents; Biological Criteria-Development By States 

Appendix D: Contributors and Reviewers 

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24 

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34 

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49 

51 

53 
Acknowledgments 

Development of this document required the combined effort of ecologists, biologists, and policy makers from States, EPA 

Regions, and EPA Headquarters. Initial efforts relied on the 1988 document Report of the National Workshop on lnstream 

Biological Monitoring and Criteria that summarizes a 1987 workshop sponsored by the EPA Office of Water Regulations and 

Standards, EPA Region V, and EPA Environmental Research Laboratory-Corvallis. In 'December 1988, contn'buting and 

reviewing committees were established (see Appendix D). Members provided reference materials and commented on drafts. 

Their assistance was most valuable. 

Special recognition goes to the Steering Committee who helped develop document goals and made a significant amtribution toward the final guidance. Members of the Steering Committee include: 

Robert Hughes, Ph.D. Chris Yoder 

Susan Davies Wayne Davis 

John Maxted Jimmie Overton 

James Plaf1cin, Ph.D. Dave Courlemanch 

Phil Larsen, Ph.D. 

Finally, our thanks go to States that recognized the importance of a biological approach in standards and pushed forward 

independently to incorporate biological criteria into their programs. Their guidance made this effort possible. 'Development of 

the program guidance document was sponsored by the U.S. EPA Office of Water Regulations and Standards and developed, in 

part, through U.S. EPA Contract No. 68-03-3533 to Dynamac Corporation. Thanks to Dr. Mark Southerland for his technical 

assistance. 

Suzanne K Macy Marcy, Ph.D. 

Editor 

In Memory of 

James L. Plafkin, Ph.D. 

iv 
Definitions 

To effectively use biological criteria, a clear understanding of how these criteria are developed and applied in a water quality standards framework is necessary. This requires, in part, that users of biological 

criteria start from the same frame of reference. To help form this frame of reference, the following definitions are provided. Please consider them carefully to ensure a consistent interpretation of this document. 

Definitions 

a An AQUATIC COMMUNITY is an association of interacting populations of aquatic organisms in a given 

waterbody or habitat. 

a A BIOLOGICAL ASSESSMENT Is an evaluation of 

the biological condition of a waterbody using biological surveys and other direct measurements of resident biota In surface waters. 

a BIOLOGICAL CRITERIA, or blocriteria, are numerical values or narrative expressions that describe the 

reference biological integrity of aquatic communities 

inhabiting waters of a given designated aquatic life 

use. 

a BIOLOGICAL INTEGRITY is functionally defined as 

the condition of the aquatic community inhabiting 

unimpaired waterbodies of a specified habitat as 

measured by community structure and function. 

a BIOLOGICAL MONITORING is the use of a biological entity as a detector and its response as a 

measure to determine environmental conditions. 

Toxicity tests and biological surveys are common 

biomonitoring methods. 

a A BIOLOGICAL SURVEY, or biosurvey, consists of 

collecting, processing and analyzing representative 

portions of a resident aquatic community to determine the community structure and function. 

a A COMMUNITY COMPONENT is any portion of a 

biological community. The community component 

may pertain to the taxomonic group (fish, invertebrates, algae), the taxonomic category (phylum, 

order, family, genus, species), the feeding strategy 

v 

(herbivore, omnivore, carnivore) or organizational 

level (individual, population, community association) 

of a biological entity within the aquatic community. 

a REGIONS OF ECOLOGICAL SIMILARITY describe 

a relatively homogeneous area defined by similarity 

of climate, landform, soil, potential natural vegetation, hydrology, or other ecologically relevant variable. Regions of ecological similarity help define the 

potential for designated use classifications of 

specific waterbodles. 

a DESIGNATED USES are those uses specified in 

water quality standards for each waterbody or segment whether or not they are being attained. 

a An IMPACT is a change in the chemical, physical or 

biological quality or condition of a waterbody caused 

by external sources. 

a An IMPAIRMENT is a detrimental effect on the 

biological integrity of a waterbody caused by an impact that prevents attainment of the designated use. 

a A POPULATION Is an aggregate of interbreeding individuals of a biological species within a specified 

location. 

a A WATER QUALITY ASSESSMENT is an evaluation 

of the condition of a waterbody using biological surveys, chemical-specific analyses of pollutants in 

waterbodies, and toxicity tests. 

a An ECOLOGICAL ASSESSMENT is an evaluation 

of the condition of a waterbody using water quality 

and physical habitat assessment methods. 
Executive Summary 

The Clean Water Act (Act) directs the U.S. Environmental Protection Agency (EPA) to develop 

programs that will evaluate, restore and maintain the chemical, physical, and biological integrity of the Nation's waters. In response to this directive, States and EPA implemented 

chemically based water quality programs that successfully addressed significant water pollution 

problems. However, these programs alone cannot identify or address all surface water pollution 

problems. To create a more comprehensive program, EPA is setting a new priority for the development of biological water quality criteria. The initial phase of this program directs State adoption of 

narrative biological criteria as part of State water quality standards. This effort will help States and 

EPA achieve the objectives of the Clean Water Act set forth in Section 101 and comp y with statutory 

requirements under Sections 303 and 304. The Water Quality Standards Regulation provides additional 

authority for biological criteria development. 

In accordance with priorities established in the FY 1991 Agency Operating Guidance, States are to 

adopt narrative biological criteria into State water quality standards during the FY 1991-1993 triennium. To support this priority, EPA is developing a Policy on the Use of Biological Assessments and 

Criteria in the Water Quality Program and is providing this program guidance document on biological 

criteria. 

This document provides guidance for development and implementation of narrative biological 

criteria. Future guidance documents will provide additional technical information to facilitate 

development and implementation of narrative and numeric criteria for each of the surface water 

types. 

When implemented, biological criteria will expand and improve water quality standards 

programs, help identify impairment of beneficial uses, and help set program priorities. Biological 

criteria are valuable because they directly measure the condition of the resource at risk, detect 

problems that other methods may miss or underestimate, and provide a systematic process for 

measuring progress resulting from the implementation of water quality programs. 

vii 
Biological Criteria: National Program Guidance 

Biological criteria require direct measurements of the structure and function of resident aquatic 

communities to determine biological integrity and ecological function. They supplement, rather than 

replace chemical and toxicological methods. It is EPA's policy that biological survey methods be fully 

integrated with toxicity and chemical-specific assessment methods and that chemical-specific criteria, 

whole-effluent toxicity evaluations and biological criteria be used as independent evaluations of nonattainment of designated uses. 

Biological criteria are narrative expressions or numerical values that describe the biological integrity of aquatic communities inhabiting waters of a given aquatic life use. They are developed 

under the assumptions that surface waters impacted by anthropogenic activities may contain impaired aquatic communities (the greater the impact the greater the expected impairment) and that 

surface waters not impacted by anthropogenic activities are generally not impaired. Measures of 

aquatic community structure and function in unimpaired surface waters functionally define biological integrity and form the basis for establishing the biological criteria. 

Narrative biological criteria are definable statements of condition or attainable goals for a given 

use designation. They establish a positive statement about aquatic community characteristics expected to occur within a waterbody (e.g., "Aquatic life shall be as it naturally occurs" or "A natural 

variety of aquatic life shall be present and all functional groups well represented"). These criteria can 

be developed using existing information. Numeric criteria describe the expected attainable community attributes and establish values based on measures such as species richness, presence or absence of indicator taxa, and distribution of classes of organisms. To implement narrative criteria and 

develop numeric criteria, biota in reference waters must be carefully assessed. These are used as the 

reference values to determine if, and to what extent, an impacted surface waterbody is impaired. 

Biological criteria support designated aquatic life use classifications for application in standards. 

The designated use determines the benefit or purpose to be derived from the waterbody; the criteria 

provide a measure to determine if the use is impaired. Refinement of State water quality standards to 

include more detailed language about aquatic life is essential to fully implement a biological criteria 

program. Data collected from biosurveys can identify consistently distinct characteristics among 

aquatic communities inhabiting different waters with the same designated use. These biological and 

ecological characteristics may be used to define separate categories within a designated use, or 

separate one designated use into two or more use classifications. 

To develop values for biological criteria, States should (1) identify unimpaired reference waterbodies to establish the reference condition and (2) characterize the aquatic communities inhabiting 

reference surface waters. Currently, two principal approaches are used to establish reference sites: (1) 

the site-specific approach, which may require upstream-downstream or near field-far field evaluations, and (2) the regional approach, which identifies similarities in the physico-chemical characteristics of watersheds that influence aquatic ecology. The basis for choosing reference sites depends 

on classifying the habitat type and locating unimpaired (minimally impacted) waters. 

viii 
Executive Summary 

Once reference sites are selected, their biological integrity must be evaluated using quantifiable 

biological surveys. 'J'.he success of the survey will depend in part on the careful selection of aquatic 

community components (e.g., fish, macroinvertebrates, algae). These components should serve as effective indicators of high biological integrity, represent a range of pollution tolerances, provide predictable, repeatable results, and be readily identified by trained State personnel. Well-planned quality 

assurance protocols are required to reduce variability in data collection and to assess the natural 

variability inherent in aquatic communities. A quality survey will include multiple community components and may be measured using a variety of metrics. Since multiple approaches are available, 

factors to consider when choosing possible approaches for assessing biological integrity are 

presented in this document and will be further developed in future technical guidance documents. 

To apply biological criteria in a water quality standards program, standardized sampling 

methods and statistical protocols must be used. These procedures must be sensitive enough to identify significant differences between established criteria and tested communities. There are three possible outcomes from hypothesis testing using these analyses: (1) the use is impaired, (2) the biological 

criteria are met, or (3) the outcome is indeterminate. If the use is impaired, efforts to diagnose the 

cause(s) will help determine appropriate action. If the use is not impaired, no action is required based 

on these analyses. The outcome will be indeterminate if the study design or evaluation was incomplete. In this case, States would need to re-evaluate their protocols. 

If the designated use is impaired, diagnosis is the next step. During diagnostic evaluations three 

main impact categories must be considered: chemical, physical, and biological stress. Two questions 

are posed during initial diagnosis: (1) what are obvious potential causes of impairment, and (2) what 

possible causes do the biological data suggest? Obvious potential causes of impairment are often 

identified during normal field biological assessments. When an impaired use cannot be easily related 

to an obvious cause, the diagnostic process becomes investigative and iterative. Normally the diagnoses of biological impairments are relatively straightforward; States can use biological criteria to 

confirm impairment from a known source of impact. 

There is considerable State interest in integrating biological assessments and criteria in water 

quality management programs. A minimum of 20 States now use some form of standardized biological assessments to determine the status of biota in State waters. Of these, 15 States are developing 

biological assessments for future criteria development. Five States use biological criteria to define 

aquatic life use classifications and to enforce water quality standards. Several States have established 

narrative biological criteria in their standards. One State has instituted numeric biological criteria. 

Whether a State is just beginning to establish narrative biological criteria or is developing a fully 

integrated biological approach, the programmatic expansion from source control to resource 

management represents a natural progression in water quality programs. Implementation of biological criteria will provide new options for expanding the scope and application of ecological perspectives. 

ix 
Part I 

Program Elements 

Introduction 

The principal objectives of the Clean Water 

Act are 0

to restore and maintain the chemical, physical and biological integrity of the 

Nation's waters• (Section 101}. To achieve these objectives, EPA, States, the regulated community, and 

the public need comprehensive Information about 

the ecological integrity of aquatic environments. 

Such information will help us Identify waters requiring special protection and those that will benefit most 

from regulatory efforts. 

To meet the objectives of the Act and to comply 

with statutory requirements under Sections 303 and 

304, States are to adopt biological criteria in State 

standards. The Water Quality Standards Regulation 

provides additional authority for this effort. In accordance with the FY 1991 Agency Operating 

Guidance, States and qualified Indian tribes are to 

adopt narrative biological criteria into State water 

quality standards during the FY 1991-1993 triennium. To support this effort, EPA is developing a 

Policy on the Use of Biological Assessments and 

Criteria in the Water Quality Program and providing 

this program guidance document on biological 

criteria. 

Like other water quality criteria, biological criteria identify water quality impairments, support 

regulatory controls that address water quality 

problems, and assess improvements In water 

quality from regulatory efforts. Biological criteria are 

numerical values or narrative expressions that 

describe the reference biological integrity of aquatic 

communities inhabiting waters of a given designated aquatic life use. They are developed through 

3 

Anthropogenic impacts, including point source 

discharges, nonpoint runoff, and habitat degradation 

continue to impair the nation's surface waters. 

the direct measurement of aquatic community components Inhabiting unimpaired surface waters. 

Biological criteria complement current programs. Of the three objectives identified in the Act 

(chemical, physical, and biological integrity), current 

water quality programs focus on direct measures of 
Blo/og/cal Criteria: National Program Guidance 

chemical Integrity (chemical-specific and whole-effluent toxicity) and, to some degree, physical Integrity through several conventional criteria (e.g., 

pH, turbidity, dissolved oxygen). Implementation of 

these programs has significantly improved water 

quality. However, as we learn more about aquatic 

ecosystems It is apparent that other sources of 

waterbody impairment exist. Biological impairments 

from diffuse sources and habitat degradation can be 

greater than those caused by point source discharges (Judy et al. 1987; Miller et al. 1989). In Ohio, 

evaluation of lnstream biota Indicated that 36 percent of Impaired stream segments could not be 

detected using chemical criteria alone (see Fig. 1 ). 

Although effective for their purpose, chemicalspecific criteria and whole-effluent toxicity provide 

only Indirect evaluations and protection of biological 

integrity (see Table 1). 

To effectively address our remaining water 

quality problems we need to develop more Integrated and comprehensive evaluations. Chemical 

and physical Integrity are necessary, but not sufficient conditions to attain biological integrity, and 

only when chemical, physical, and biological Integrity are achieved, is ecological Integrity possible 

(see Fig. 2). Biological criteria provide an essential 

third element for water quality management and 

serve as a natural progression In regulatory 

programs. Incorporating biological criteria into a 

fully Integrated program directly protects the biological Integrity of surface waters and provides Indirect 

protection for chemical and physical integrity (see 

Table 2). Chemical-specific criteria, whole-effluent 

toxicity evaluations, and biological criteria, when 

used together, complement the relative strengths 

and weaknesses of each approach. 

Figure 1.-0hlo Blosurvey Results Agree with 

lnstream Chemistry or Reveal Unknown Problems 

Impairment Identification 

Chemical Prediction 

& Biosurvey Agree 

__. ......... __ 

58% 

Biosurvey Show No 

Impairment; Chemical 

Evaluation Indicates 

Impairment 

Fig. 1: In an intensive survey, 431 sites in Ohio were assessed 

using lnstream chemistry and biological surveys. In 36% of 

the cases, chemical evaluations implied no impairment but 

biological survey evaluations showed impairment. In 58% of 

the cases the chemical and biological assessments agreed. 

Of these, 17% identified waters with no impairment, 41 % 

identified waters which were considered impaired. (Modified 

from Ohio EPA Water Quality Inventory, 1988.) 

Biological assessments have been used in 

biomonitoring programs by States for many years. 

In this respect, biological criteria support ear1ier 

work. However, implementing biological criteria in 

water quality standards provides a systematic, 

structured, and objective process for making 

decisions about compliance with water quality 

standards. This distinguishes biological criteria from 

earlier use of biological Information and Increases 

the value of biological data in regulatory programs. 

Table 1.-Current Water Quality Program Protection of the Three Elements of Ecological Integrity. 

ELEMENTS OF ECOLOGICAL PROGRAM THAT DIRECTLY PROGRAM THAT INDIRECTLY 

INTEGRITY PROTECTS PROTECTS 

Chemical Integrity Chemical Specific Criteria (toxics) 

Whole Effluent Toxicity (toxics) 

Physical Integrity Criteria for Conventionals 

(oH, DO, turbidity) 

Biological Integrity Chemical/Whole Effluent Toxicity 

(biotic response in lab) 

Table 1: Current programs focus on chemical specific and whole-effluent toxicity evaluations. aoth are valuable approaches 

for the direct evaluation and protection of chemical integrity. Physical integrity is also directly protected to a limited degree 

through criteria for conventional pollutants. Biological integrity is only indirectly protected under the assumption that by 

evaluating toxicity to organisms in laboratory studies, estimates can be made about the toxicity to other organisms inhabiting 

ambient waters. 

4 
Chapter 1: Introduction 

Table 2.-Water Quality Programs that Incorporate Blologlcal Criteria to Protect Elements of Ecological Integrity. 

ELEMENTS OF 

ECOLOGICAL INTEGRITY DIRECTLY f>ROTECTS INDIRECTLY PROTECTS 

Chemical Integrity Chemical Specific Criteria (toxics) Biocriteria (identification of 

Whole Effluent Toxicity (toxics) impairment) 

Physical Integrity Criteria for conventionals (pH, temp., Biocriteria (habitat evaluation) 

DO) 

Biological Integrity Biocriteria (biotic response in surface Chemical/Whole Effluent Testing 

water) (biotic response in lab) 

Table 2: When biological criteria are incorporated into water quality programs the biological integrity of surface waters may 

be directly evaluated and protected. Biological criteria also provide additional benefits by requiring an evaluation of physical 

integrity and providing a monitoring tool to assess the effectiveness of current chemically based criteria. 

Figure 2.-The Elements of Ecological Integrity 

Chemical 

Integrity 

Biological 

Integrity 

Fig. 2: Ecological Integrity is attainable when chemical, 

physical, and biological integrity occur simultaneously. 

Value of Biological 

Criteria 

Biological criteria provide an effective tool for 

addressing remaining water quality problems by 

directing regulatory efforts toward assessing the 

biological resources at risk from chemical, physical 

or biological impacts. A primary strength of biological criteria is the detection of water quality problems 

that other methods may miss or underestimate. 

Biological criteria can be used to determine to what 

extent current regulations are protecting the use. 

s 

Biological assessments provide integrated 

evaluations of water quality. They can identify impairments from contamination of the water column 

and sediments from unknown or unregulated chemicals, non-chemical impacts, and altered physical 

habitat. Resident biota function as continual 

monitors of environmental quality, increasing the 

likelihood of detecting the effects of episodic events 

(e.g., spills, dumping, treatment plant malfunctions, 

nutrient enrichment), toxic nonpoint source pollution 

(e.g., agricultural pesticides), cumulative pollution 

(i.e., multiple impacts over time or continuous lowlevel stress), or other impacts that periodic chemical 

sampling is unlikely to detect. Impacts on the physical habitat such as sedimentation from stormwater 

runoff and the effects of physical or structural 

habitat alterations (e.g., dredging, f~ling, channelization) can also be detected. 

Biological criteria require the direct measure of 

resident aquatic community structure and function 

to determine biological integrity and ecological function. Using these measures, impairment can be 

detected and evaluated without knowing the impact(s) that may cause the impairment. 

Biological criteria provide a regulatory framework for addressing water quality problems and 

offer additional benefits, including providing: 

• the basis for characterizing high quality 

waters and identifying habitats and 

community components requiring special 

protection under State anti-degradatioh 

policies; 

• a framework for deciding 319 actions for best 

control of nonpoint source pollution; 

• an evaluation of surface water impairments 

predicted by chemical analyses, toxicity 
Blolog/ca/ Critllrla: Nalional Program Guidance 

testing, and fate and transport modeling {e.g., 

wasteload allocation);. 

• Improvements In water quality standards 

(including refinement of use classifications); 

• a process for demonstrating improvements in 

water quality after implementation of pollution 

controls; 

• additional diagnostic tools. 

The role of biological criteria as a regulatory tool 

is being realized in some States (e.g., Arkansas, 

Maine, Ohio, North Carolina, Vermont). Biological 

assessments and criteria have been useful for 

regulatory, resource protection, and monitoring and 

reporting programs. By incorporating biological 

criteria in programs, States can improve standards 

setting and enforcement, measure impairments 

from permit violations, and refine wasteload allocation models. In addition, the location, extent, and 

type of biological Impairments measured in a waterbody provide valuable information needed for identifying the cause of impairment and determining 

actions required to improve water quality. Biological 

assessment and criteria programs provide a costeffective method for evaluating water quality when a 

standardized, systematic approach to study design, 

field methods, and data analysis is established 

(Ohio EPA 1988a). 

Process for 

Implementation 

The implementation of biological criteria will follow the same process used for current chemicalspecific and whole-effluent toxicity applications: national guidance produced by U.S. EPA will support 

States working to establish State standards for the 

implementation of regulatory programs (see Table 

3). Biological criteria differ, however, in the degree 

of State involvement required. Because surface 

waters vary significantly from region to region, EPA 

will provide guidance on acceptable approaches for 

biological criteria development rather than specific 

criteria with numerical limitations. States are to establish assessment procedures, conduct field 

evaluations, and determine criteria values to implement biological criteria in State standards and apply 

them in regulatory programs. 

The degree of State involvement required influences how biological criteria will be Implemented. 

It is expected that States will implement these 

criteria in phases. 

• Phase I includes the development and adoption of narrative biological criteria into State 

standards for all surface waters (streams, 

rivers, lakes, wetlands, estuaries). Definitions 

of terms and expressions in the narratives 

must be- included in these standards (see the 

Narrative Criteria Section, Chapter 3). Adoption of narrative biological criteria in State 

standards provides the legal and programmatic basis for using ambient biological surveys and assessments in regulatory actions. 

• Phase II includes· the development of an implementation plan. The plan should include 

program objectives, study design, research 

protocols, criteria for selecting reference conditions and community components, quality 

assurance and quality control procedures, 

Table 3.-Process for Implementation of Water Quality Standards. 

CRITERIA 

Chemical Specific 

Narrative Free Forms 

Biological 

EPA GUIDANCE 

Pollutant specific numeric criteria 

Whole effluent toxicity guidance 

Biosurvey minimum requirement 

guidance 

STATE IMPLEMENTATION 

State Standards 

• use designation 

• numeric criteria 

• antidegradation 

Water Quality Narrative 

• no toxic amounts translator 

State Standards 

• refined use 

• narrative/numeric criteria 

• antidegradation 

STATE APPLICATION 

Permit limits Monitoring 

Best Management Practices 

Wasteload allocation 

Permit limits Monitoring 

Wasteload allocation 

Best Management Practices 

Permit conditions Monitoring 

Best Management Practices 

Wasteload allocation 

Table 3: ~imilar t? ch~micai. sp~c~fic criteria and whole effluent toxicity evaluations, EPA is providing guidance to States for 

the adoption of b1olog1cal cntena into State standards to regulate sources of water quality impairment. 

6 
and training for State personnel. In Phase II, 

States are to develop plans necessary to implement biological criteria for each surface 

water type. 

• Phase Ill requires full Implementation and Integration of biological criteria in water quality 

standards. This requires using biological surveys to derive biological criteria for classes of 

surface waters and designated uses. These 

criteria are then used to Identify nonattainment of designated uses and make regulatory 

decisions. 

Narrative biological criteria can be developed 

for all five surface water classifications with little or 

no data collection. Application of narrative criteria in 

seriously degraded waters is possible in the short 

term. However, because of the diversity of surface 

waters and the biota that Inhabit these waters, significant planning, data collection, and evaluation will 

be needed to fully implement the program. Criteria 

for each type of surface water are likely to be 

developed at different rates. The order and rate of 

development will depend, in part, on the development of EPA guidance for specific types of surface 

water. Biological criteria technical guidance for 

streams will be produced during FY 1991. The tentative order for future technical guidance documents 

includes guidance for rivers (FY 1992), lakes (FY 

1993), wetlands (FY 1994) and estuaries (FY 1995). 

This order and timeline for guidance does not reflect 

the relative importance of these surface waters, but 

rather indicates the relative availability of research 

and the anticipated difficulty of developing 

guidance. 

Independent Application 

of Biological Criteria 

Biological criteria supplement, but do not 

replace, chemical and toxicological methods. Water 

chemistry methods are necessary to predict risks 

(particularly to human health and wildlife), and to 

diagnose, model, and regulate important water 

quality problems. Because biological criteria are 

able to detect different types of water quality impairments and, in particular, have different levels of sensitiVity for detecting certain types of impairment 

7 

Chapter 1: Introduction 

compared to toxicological methods, they are not 

used in lieu of, or in conflict with, current regulatory 

efforts. 

As with all criteria, certain limitations to biological criteria make independent application essential. 

Study design and use influences how sensitive 

biological criteria are for detecting community impairment. Several factors influence sensitivity: (1) 

State decisions about what is significantly different 

between reference and test communities, (2) study 

design, which may include community components 

that are not sensitive to the impact causing Impairment, (3) high natural variability that makes it difficult to detect real differences, and (4) types of 

impacts that may be detectable sooner by other 

methods (e.g., chemical criteria may provide earlier 

indications of impairment from a bioaccumulative 

chemical because aquatic communities require exposure over time to incur the full effect). 

Since each type of criteria (biological criteria, 

chemical-specific criteria, or whole-effluent toxicity 

evaluations) has different sensitivities and purposes, a criterion may fail to detect real impairments 

when used alone. As a result, these methods should 

be used together in an integrated water quality assessment, each providing an independent evaluation of nonattainment of a designated use. If any 

one type of criteria indicates impairment of the surface water, regulatory action can be taken to improve water quality. However, no one type of criteria 

can be used to confirm attainment of a use if 

another form of criteria indicates nonattainment 

(see Hypothesis Testing: Biological Criteria and the 

Scientific Method, Chapter 7). When these three 

methods are used together, they provide a powerful, 

integrated, and effective foundation for waterbody 

management and regulations. 

How to Use this 

Document 

The purpose of this document is to provide EPA 

Regions,· States and others with the conceptual 

framework and assistance necessary to develop 

and implement narrative and numeric biological 

criteria and to promote national consistency in application. There are two main parts of the document. 

Part One (Chapters 1, 2, 3, and 4) includes the essential concepts about what biological criteria are 
Blologlcal Criteria: Nallona/ Program Guldsnce 

and how they are used In regulatory programs. Part 

Two (Chapters 5, 6, and 7) provides an overview of 

the process that Is essential for Implementing a 

State biological criteria program. Specific chapters 

include the following: 

Part I: PROGRAM ELEMENTS 

a Chapter 2, Legal Authority, reviews the legal 

basis for biological criteria under the Clean 

Water Act and includes possible applications 

under the Act and other legislation. 

a Chapter 3, Conceptual Framework, 

discusses the essential program elements for 

biological criteria, including what they are and 

how they are developed and used within a 

regulatory program. The development of 

narrative biological criteria Is discussed in this 

chapter. 

a Chapter 4, Integration, discusses the use of 

biological criteria in regulatory programs. 

Part II: THE IMPLEMENTATION PROCESS 

a Chapter 5, The Reference Condition, 

provides a discussion on alternative forms of 

reference conditions that may be developed by 

a State based on circumstances and needs. 

a Chapter 6, The Blologlcal Survey, provides 

some detail on the elements of a quality 

biological survey. 

a Chapter 7, Hypothesis Testing: Biological 

Criteria and the Scientific Method, discusses 

how biological surveys are used to make 

regulatory and diagnostic decisions. 

a Appendix A Includes commonly asked 

questions and their answers about biological 

criteria. 

8 

Two additional documents are planned in the 

near term to supplement this program guidance 

document. 

1. •Biological Criteria Technical Reference 

Guide" will contain a cross reference of technical papers on available approaches and 

methods for developing biological criteria 

(see tentative table of contents in Appendix 

B), 

2. •Biological Criteria Development by States" 

will provide a summary of different mechanisms several States have used to implement 

and apply biological criteria in water quality 

programs (see tentative outline in Appendix 

C). 

Both documents are planned for FY 1991. As 

previously discussed, over the next triennlum technical guidance for specific systems (e.g., streams, 

wetlands) will be developed to provide guidance on 

acceptable biological assessment procedures to further support State implementation of comprehensive programs. 

This biological criteria program guidance document supports development and Implementation of 

biological criteria by providing guidance to States 

working to comply with requirements under the 

Clean Water Act and the Water Quality Standards 

Regulation. This guidance is not regulatory. 

I 
-

Legal Authority 

The Clean Water Act (Federal Water Pollution 

Control Act of 1972, Clean Water Act of 

1977, and the Water Quality Act of 1987) 

mandates State development of criteria based on 

biological assessments of natural ecosystems. 

The g eneral authority for biological criteria 

comes from Section 101 (a) of the Act which establishes as the objective of the Act the restoration and 

maintenance of the chemical, physical, and biological integrity of the Nation's waters. To meet this objective, water quality criterf a must include criteria to 

protect biological integrity. Section 101 (a)(2) includes the interim water quality goal for the protection and propagation of fish, shellfish, and wildlife. 

Propagation includes the full range of biological 

conditions necessary to support reproducing 

population'S of all forms of aquatic life and other life 

that depend on aquatic systems. Sections 303 and 

304 provide specific directives for the development 

of biological criteria. 

Secti<>n 303 

Under Section 303{c) of the Act, States are required to adopt protective water quality standards 

that consist of uses, criteria, and antidegradation. 

States are- to review these standards every three 

years and to revise them as needed. 

Sectio11 303(c) (2) (A) requires the adoption of 

water quallity standards that • ... serve the purposes 

of the Act,• as given in Section 101. Section 

303(c)(2)(E), enacted in 1987, requires States to 

9 

Balancing the legal authority for biological criteria. 

adopt numeric criteria for toxic pollutants for which 

EPA has published 304(a) (1) criteria. The section 

further requires that, where numeric 304(a) criteria 

are not available, States should adopt criteria based 

on biological assessment and monitoring methods, 

consistent with information l)Ublished by EPA under 

304(a)(8). 

These specific directives do not serve to restrict 

the use of biological criteria in other settings where 

they may be helpful. Accordingly, this guidance 

document provides assistance in implementing 

various sections of the Act, not just 303(c) (2) (B). 
Biological CrltBrla: National Program Guidance 

Section 304 

Section 304(a) directs EPA to develop and 

publish water quality criteria and information on 

methods for measuring water quality and establishing water quality criteria for toxic pollutants on 

bases other than pollutant-by-pollutant, Including 

biological monitoring and assessment methods 

which assess: 

• the effects of pollutants on aquatic community 

components (" ... plankton, fish, shellfish, 

wildlife, plant life ... ") and community 

attributes (

0 

••• biological community diversity, 

productivity, and stability .. ."); in any body of 

water and;· 

• factors necessary " ... to restore and 

maintain the chemical, physical, and 

biological integrity of all navi!,lable waters ... • 

for• ... the protection of shellfish, fish, and 

wildlife for classes and categories of receiving 

waters ... • 

Potential Applications 

Under the Act 

Development and use of biological criteria will 

help States to meet other requirements of the Act, 

including: 

o setting planning and management priorities for 

waterbodies most in need of controls 

[Sec. 303(d)]; 

o determining impacts from nonpoint sources 

[i.e., Section 304(f) ·c1) guidelines for 

identifying and evaluating the nature and 

extent of nonpoint sources of pollutants, and 

(2) processes, procedures, and methods to 

control pollution .. .-1. 

IJ biennial reports on the extent to which waters 

support balanced biological communities 

[Sec. 305(b)]; 

o assessment of lake trophic status and trends 

[Sec. 314]; 

10 

IJ lists of waters that cannot attain designated 

uses without nonpolnt source controls 

[Sec. 319]; 

o development of management plans and 

conducting monitoring in estuaries of national 

significance [Sec. 320]; 

IJ issuing permits for ocean discharges and 

monitoring ecological effects [Sec. 403(c) and 

301 (h)(3)]; 

IJ determination of acceptable sites for disposal. 

of dredge and fill material [Sec. 404]; 

Potential Applications 

Under Other Legislation 

Several legislative acts require an assessment 

of risk to the environment (including resident aquatic 

communities) to determine the need for regulatory 

action. Biological criteria can be used in this context 

to support EPA assessments under: 

o Toxic Substances Control Act (TSCA) of 1976 

o Resource Conservation and Recovery Act 

(RCRA), 

!J Comprehensive Environmental Response, 

Compensation and Liability Act of 1980 

(CE RC LA), 

tl Superfund Amendments and Reauthorization 

Act of 1986 (SARA), 

tl Federal Insecticide, Fungicide, and 

Rodenticide Act (FIFRA); 

o National Environmental Policy Act (NEPA); 

o Federal Lands Policy and Management Act 

(FLPMA). 

o The Fish and Wildlife Conservation Act of 1980 

o Marine Protection, Research, and Sanctuaries 

Act 

o Coastal Zone Management Act 
o Wild and Scenic Rivers Act 

o Fish and Wildlife Coordination Act, as 

Amended in 1965 

A summary of the applicability of these Acts for 

assessing ecological impairments may be found in 

Risk Assessment Guidance for Superfund-Environmental Evaluation Manual (Interim Final) 1989. 

Other federal and State agencies can also 

benefit from using biological criteria to evaluate the 

biological integrity of surface waters within their 

jurisdiction and to the effects of specific practices on 

surface water quality. Agencies that could benefit include: 

o Department of the Interior (U.S. Fish and 

Wildlife Service, U.S. Geological Survey, 

Bureau of Mines, and Bureau of Reclamation, 

Bureau of Indian Affairs, Bureau of Land 

Manelgement, and National Park Service), 

o Department of Commerce (National Oceanic 

and Atmospheric Administration, National 

Marine Fisheries Service), 

o Department of Transportation (Federal 

High way Administration) 

o Department of Agriculture (U.S. Forest 

Service, Soil Conservation Service) 

o Department of Defense, 

o Oep'1rtment of Energy, 

o Army Corps of Eng lneers, 

o Tennessee Valley Authority. 

Chapter 2: Legal Authority 

11 

-

The Conceptual Framework 

B iological integrity and the determination of 

use impairment through assessment of ambient biological communities form the foundation for biological criteria development. The 

effectiveness of a biological criteria program will 

depend on the development of quality criteria, the 

refinement of use classes to support narrative 

criteria, and careful application of scientific principles. 

Premise for Biological 

Criteria 

Biological criteria are based on the premise that 

the structure and function of an aquatic biological 

community within a specific habitat provide critical 

information about the quality of surface waters. Existing aquatic communities in pristine environments 

not subject to anthropogenic impact exemplify 

biological integrity and serve as the best possible 

goal for water quality. Although pristine environments are virtually non-existent (even remote 

waters are impacted by air pollution}, minimally impacted waters exist. Measures of the structure and 

function of aquatic communities inhabiting unimpaired (minimally impacted} waters provide the 

basis for establishing a reference condition that may 

be compared to the condition of impacted surface 

waters to determine impairment. 

Based on this premise, biological criteria are 

developed under the assumptions that: (1) surface 

waters subject to anthropogenic disturbance may 

contain impaired populations or communities of 

aquatic organisms-the greater the anthropogenic 

13 

Aquatic communities assessed in unimpaired 

waterbodies (top) provide a reference for evaluating 

impairments in the same or similar waterbodies suffering 

from Increasing anthropogenic impacts (bottom). 
Biological Criteria: Nallonal Program Guidance 

disturbance, the greater the likelihood and magnitude of impairment; and (2) surface waters not 

subject to anthropogenic disturbance generally contain unimpaired (natural) populations and communities of aquatic organisms exhibiting biological 

integrity. 

Biological Integrity 

The expression "biological integrity" is used in 

the Clean Water Act to define the Nation's objectives for water quality. According to Webster's New 

World Dictionary (1966), integrity is, "the quality or 

state of being complete; unimpaired." Biological integrity has been defined as "the ability of an aquatic 

ecosystem to support and maintain a balanced, integrated, adaptive community of organisms having 

a species composition, diversity, and functional organization comparable to that of the natural habitats 

within a region" (Karr and Dudley 1981). For the purposes of biological criteria, these concepts are combined to develop a functional definition for 

evaluating biological integrity in water quality 

programs. Thus, biological integrity is functionally 

defined as: 

the condition of the aquatic community 

inhabiting the unimpaired waterbodies 

of a specified habitat as measured by 

community structure and function. 

It will often be difficult to find unimpaired waters 

to define biological integrity and establish the reference condition. However, the structure and function 

of aquatic communities of high quality waters can be 

approximated in several ways. One is to characterize aquatic communities in the most protected 

waters representative of the regions where such 

sites exist. In areas where few or no unimpaired 

sites are available, characterization of least impaired systems approximates unimpaired systems. 

Concurrent analysis of historical records should 

supplement descriptions,of the condition of least impaired systems. For some systems, such as lakes, 

evaluating paleoecological information (the record 

stored in sediment profiles) can provide a measure 

of less disturbed conditions. 

Surface waters, when inhabited by aquatic communities, are exhibiting a degree of biological integrity. However, the best representation of 

biological integrity for a surface water should form 

14 

the basis for establishing water quality goals for 

those waters. When tied to the development of 

biological criteria, the realities of limitations on 

biological integrity can be considered and incorporated into a progressive program to improve 

water quality. 

Biological Criteria 

Biological criteria are narrative expressions or 

numerical values that describe the biological integrity of aquatic communities inhabiting waters of a 

given designated aquatic life use. While biological 

integrity describes the ultimate goal for water 

quality, biological criteria are based on aquatic community structure and function for waters within a 

variety of designated uses. Designated aquatic life 

uses serve as general statements of attained or attainable uses of State waters. Once established for 

a designated use, biological criteria are quantifiable 

values used to determine whether a use is impaired, 

and if so, the level of impairment. This is done by 

specifying what aquatic community structure and 

function should exist in waters of a given designated 

use, and then comparing this condition with the condition of a site under evaluation. If the existing 

aquatic community measures fail to meet the 

criteria, the use is considered impaired. 

Since biological surveys used for biological 

criteria are capable of detecting water quality 

problems (use impairments) that may not be 

detected by chemical or toxicity testing, violation of 

biological criteria is sufficient cause for States to initiate regulatory action. Corroborating chemical and 

toxicity testing data are not required (though they 

may be desirable) as supporting evidence to sustain 

a determination of use impairment. However, a finding that biological criteria fail to indicate use impairment does not mean the use is automatically 

attained. Other evidence, such as violation of physical or chemical criteria, or results from toxicity tests, 

can also be used to identify impairment. Alternative 

forms of criteria provide independent assessments 

of nonattainment. 

As stated above, biological criteria may be narrative statements or numerical values. States can 

establish general narrative biological criteria early in 

program development without conducting biological 

assessments. Once established in State standards, 

narrative biological criteria form the legal and 
programmatic basis for expanding biological assessment and biosurvey programs needed to implement narrative criteria and develop numeric 

biological criteria. Narrative biological criteria 

should become part of State regulations and standards. 

Narrative Criteria 

Narrative biological criteria are general statements of attainable or attained conditions of biological integrity and water quality for a given use 

designation. Although similar to the "free from" 

chemical water quality criteria, narrative biological 

criteria establish a positive statement about what 

should occur within a water body. Narrative criteria 

can take a number of forms but they must contain 

several attributes to support the goals of the Clean 

Water Act to provide for the protection and propagation of fish, shellfish, and wildlife. Thus, narrative 

criteria should include specific language about 

aquatic community characteristics that (1) must 

exist in a waterbody to meet a particular designated 

aquatic life use, and (2) are quantifiable. They must 

be written to protect the use. Supporting statements 

for the criteria should promote water quality to 

protect the most natural community possible for the 

designated use. Mechanisms should be established 

in the standard to address potentially conflicting 

multiple uses. Narratives should be written to 

Chapter 3: The Conceptual Framework 

protect the most sensitive use and support antidegradation. 

Several States currently use narrative criteria. 

In Maine, for example, narrative criteria were established for four classes of water quality for streams 

and rivers (see Table 4). The classifications were 

based on the range of goals in the Act from •no discharge• to "protection and propagation of fish, 

shellfish, and wildlife" (Courtemanch and Davies 

1987). Maine separated its "high quality water• into 

two categories, one that reflects the highest goal of 

the Act (no discharge, Class AA) and one that 

reflects high integrity but is minimally impacted by 

human activity (Class A). The statement "The 

aquatic life ... shall be as naturally occursM is a narrative biological criterion for both Class AA and A 

waters. Waters in Class B meet the use when the 

life stages of all indigenous aquatic species are supported and no detrimental changes occur in community composition (Maine DEP 1986). These 

criteria directly support refined designated aquatic 

life uses (see Section D, Refining Aquatic Life Use 

Classifications). 

These narrative criteria are effective only if, as 

Maine has done, simple phrases such as "as 

naturally occurs• and "nondetrimental" are clearly 

operationally defined. Rules for sampling procedures and data analysis and interpretation should 

become part of the regulation or supporting 

documentation. Maine was able to develop these 

criteria and their supporting statements using availTable 4.-Aquatlc Life Classitlcatlon Scheme for Maine's Rivers and Streams. 

RIVERS AND 

STREAMS MANAGEMENT PERSPECTIVE 

Class AA High quality water for preservation of 

recreational and ecological interests. No 

discharges of any kind permitted. No 

impoundment permitted. 

Class A High quality water with limited human 

interference. Discharges restricted to noncontact 

process water or highly treated wastewater of 

quality equal to or better than the receiving 

water. lmpoundment permitted. 

Class B Good quality water. Discharges of well treated 

effluents with ample dilution permitted. 

Class C Lowest quality water. Requirements consistent 

with interim goals of the federal Water Quality 

Law (fishable and swimmable). 

15 

LEVEL OF BIOLOGICAL INTEGRITY 

Aquatic life shall be as naturally occurs. 

Aquatic life shall be as naturally occurs. 

Ambient water quality sufficient to support life 

stages of all indigenous aquatic species. Only 

nondetrimental changes in community 

composition may occur. 

Ambient water quality sufficient to support the 

life stages of all indigenous fish species. 

Changes in species composition may occur but 

structure and function of the aquatic community 

must be maintained. 
Blo/oglcal Criteria: National Program Guidance 

able data from water quality programs. To implement the criteria, aquatic life inhabiting unimpaired 

waters must be measured to quantify the criteria 

statement. 

Narrative criteria can take more specific forms 

than Illustrated in the Maine example. Narrative 

criteria may include specific classes and species of 

organisms that will occur In waters for a given designated use. To develop these narratives, field evaluations of reference conditions are necessary to 

identify biological community attributes that differ 

significantly between designated uses. For example 

in th~ Arkansas use class Typical Gulf Coastal 

Ecoregion (i.e., South Central Plains) the narrative 

criterion reads: 

"Streams supporting diverse 

communities of indigenous or adapted 

species of fish and other forms of 

aquatic life. Fish communities are 

characterized by a limited proportion of 

sensitive species; sunfishes are 

distinctly dominant, followed by darters 

and minnows. The community may be 

generally characterized by the following 

fishes: Key Specles-Redfin shiner, 

Spotted sucker, Yellow bullhead, Flier, 

Slough darter, Grass pickerel; Indicator 

Species-Pirate perch, Warmouth, 

Spotted sunfish, Dusky darter, Creek 

chubsucker, Banded pygmy sunfish 

(Arkansas DPCE 1988). 

In Connecticut, current designated uses are 

supported by narratives in the standard. For example, under Surface Water Classifications, Inland 

Surface Waters Class AA, the Designated Use is: 

"Existing or proposed drinking water supply; fish 

and wildlife habitat; recreational use; agricultural, industrial supply, and other purposes (recreation uses 

may be restricted).• 

The supporting narratives include: 

Benthlc Invertebrates which inhabit lotlc 

waters: A wide variety of 

macroinvertebrate taxa should normally 

be present and all functional groups 

should normally be well represented ... 

Water quality shall be sufficient to 

sustain a diverse macroinvertebrate 

community of Indigenous species. Taxa 

within the Orders Plecoptera 

16 

(stoneflies), Ephemeroptera (mayflies), 

Coleoptera (beetles), Tr/copters 

(caddisflies) should be well represented 

(Connecticut DEP 1987). 

For these narratives to be effective in a biological criteria program expressions such as •a wide 

variety• and "functional groups should normally be 

well represented" require quantifiable definitions 

that become part of the standard or supporting 

documentation. Many States may find such narratives in their standards already. If so, States should 

evaluate current language to determine if it meets 

the requirements of quantifiable narrative criteria 

that support refined aquatic life uses. 

Narrative biological criteria are similar to the 

traditional narrative "free froms• by providing the 

legal basis for standards applications. A sixth "free 

from" could be incorporated into standards to help 

support narrative biological criteria such as "free 

from activities that would impair the aquatic community as it naturally occurs.• Narrative biological 

criteria can be used immediately to address obvious 

existing problems. 

Numeric Criteria 

Numerical indices that serve as biological 

criteria should describe expected attainable community attributes for different designated uses. It is 

important to note that full implementation of narrative criteria will require similar data as that needed 

for developing numeric criteria. At this time, States 

may or may not choose to establish numeric criteria 

but may find it an effective tool for regulatory use. 

To derive a numeric criterion, an aquatic community's structure and function is measured at reference sites and set as a reference condition. 

Examples of relative measures include similarity indices, coefficients of community loss, and comparisons of lists of dominant taxa. Measures of 

existing community structure such as species richness, presence or absence of indicator taxa, and 

distribution of trophic feeding groups are useful for 

establishing the normal range of community components to be expected in unimpaired systems. For 

example, Ohio uses criteria for the warmwater 

habitat use class based on multiple measures in different reference sites within the same ecoregion. 

Criteria are set as the 25th percentile of all biological index scores recorded at established reference 
sites within the ecoregion. Exceptional warmwater 

habitat index criteria are set at the 75th percentile 

(Ohio EPA 1988a). Applications such as this require 

an extensive data base and multiple reference sites 

for each criteria value. 

To develop numeric biological criteria, careful 

assessments of biota in reference sites must be 

conducted (Hughes et al. 1986). There are 

numerous ways to assess community structure and 

function in surface waters. No single index or 

measure is universally recognized as free from bias. 

It is important to evaluate the strengths and weaknesses of different assessment approaches. A multimetric approach that incorporates information on 

species richness, trophic composition, abundance 

or biomass, and organism condition Is recommended. Evaluations that measure multiple components of communities are also recommended 

because they tend to be more reliable (e.g., 

measures of fish and macroinvertebrates combined 

will provide more information than measures of fish 

communities alone). The weaknesses of one 

measure or index can often be compensated by 

combining it with the strengths of other community 

measurements. 

The particular indices used to develop numeric 

criteria depend on the type of surface waters 

(streams, rivers, lakes, Great Lakes, estuaries, wetlands, and nearshore marine) to which they must be 

applied. In general, community-level indices such 

as the Index of Biotic Integrity developed for midwestem streams (Karr et al. 1986) are more easily 

interpreted and less variable than fluctuating numbers such as population size. Future EPA technical 

guidance documents will include evaluations of the 

effectiveness of different biological survey and assessment approaches for measuring the biological 

integrity of surface water types and provide 

guidance on acceptable approaches for biological 

criteria development. 

Refining Aquatic Life Use 

Classifications 

State standards consist of (1) designated 

aquatic life uses, (2) criteria sufficient to protect the 

designated and existing use, and (3) an antidegradatlon clause. Biological criteria support 

designated aquatic life use classifications for application In State standards. Each State develops its 

17 

Chapter 3: The Conceptual Fram11Work 

own designated use classification system based on 

the generic uses cited in the Act (e.g., protection 

and propagation of fish, shellfish, and wildlife). 

Designated uses are intentionally general. However, States may develop subcategories within use 

designations to refine and clarify the use class. 

Clarification of the use class is particularly helpful 

when a variety of surface waters with distinct characteristics fit within the same use class, or do not fit 

well into any category. Determination of nonattainment in these waters may be difficult and open to alternative interpretations. If a determination is in 

dispute, regulatory actions will be difficult to accomplish. Emphasizing aquatic community structure 

within the designated use focuses the evaluation Of 

attainment/nonattainment on the resource of concern under the Act. 

Flexibility inherent in the State process for 

designating uses allows the development of subcategories of uses within the Act's general 

categories. For example, subcategories of aquatic 

life uses may be on the basis of attainable habitat 

(e.g., cold versus warmwater habitat); innate differences In community structure and function, (e.g., 

high versus low species richness or productivity); or 

fundamental differences in important community 

components (e.g., warmwater fish communities 

dominated by bass versus catfish). Special uses 

may also be designated to protect particularly unique, sensitive, or valuable aquatic species, communities, or habitats. 

Refinement of use classes can be accomplished within current State use classification 

structures. Data collected from biosurveys as part of 

a developing blocriteria program may reveal unique 

and consistent differences among aquatic communities inhabiting different waters with the same 

designated use. Measurable biological attributes 

could then be used to separate one class into two or 

more classes. The result is a refined aquatic life 

use. For example, in Arkansas the beneficial use 

Fisheries "provides for the protection and propagation of fish, shellfish, and other forms of aquatic life" 

(Arkansas DPCE 1988). This use is subdivided into 

Trout, Lakes and Reservoirs, and Streams. Recognizing that stream characteristics across regions of 

the State differed ecologically, the State further subdivided the stream designated uses into eight additional uses based on regional characteristics (e.g., 

Springwater-influenced Gulf Coastal Ecoregion, 

Ouachita Mountains Ecoregion). Within this classification system, it was relatively straightforward for 
Biological Criteria: NatJona/ Program Guidance 

Arkansas to establish detailed narrative biological 

criteria that list aquatic community components expected In each ecoreglon (see Narrative Criteria 

section). These narrative criteria can then be used 

to establish whether the use Is impaired. 

States can refine very general designated uses 

such as high, medium, and low quality to specific 

categories that Include measurable ecological characteristics. In Maine, for example, Class AA waters 

are defined as "the highest classification and shall 

be applied to waters which are outstanding natural 

resources and which should be preserved because 

of their ecological, social, scenic, or recreational importance." The designated use Includes "Class AA 

waters shall be of such quality that they are suitable 

. . . as habitat for fish and other aquatic life. The 

habitat shall be characterized as free flowing and 

natural.• This use supports development of narrative criteria based on biological characteristics of 

aquatic communities (Maine DEP 1986; see the 

Narrative Criteria section). 

Biological criteria that include lists of dominant 

or typical species . expected to live In the surface 

water are particularly effective. Descriptions of impaired conditions are more difficult to interpret. 

However, biological criteria may contain statements 

concerning which species dominate disturbed sites, 

as well as those species expected at minimally impacted sites. 

Most States collect biological data in current 

programs. Refining aquatic life use classifications 

and Incorporating biological criteria Into standards 

will enable States to evaluate these data more effectively. 

Developing and 

Implementing Biological 

Criteria 

Biological criteria development and implementation in standards require an understanding of the 

selection and evaluation of reference sites, measurement of aquatic community structure and function, and hypothesis testing under the scientific 

method. The developmental process Is Important for 

State water quality managers and their staff -to understand to promote effective planning for resource 

and staff needs. This major program element deser18 

ves careful consideration and has been separated 

out in Part II by chapter for each developmental step 

as noted below. Additional guidance will be provided 

in future technical guidance documents. 

The developmental process is illustrated in Figure 3. The first step is establishing narrative criteria 

in standards. However, to support these narratives, 

standardized protocols need to be developed to 

quanitify the narratives for criteria Implementation. 

They should include data collection procedures, 

selection of reference sites, quality assurance and 

quality control procedures, hypothesis testing, and 

statistical protocols. Pilot studies should be conducted using these standard protocols to ensure 

they meet the needs of the program, test the 

hypotheses, and provide effective measures of the 

biological integrity of surface waters In the State. 

Figure 3.-Process for the Development and 

Implementation of Biological Criteria 

Develop Standard Protocols 

(Test protocol sensitivity) 

+ Identify and Conduct Biosurveys at 

Unimpaired Reference Sites 

+ Establish Biological Criteria 

+ Conduct Biosurveys at Impacted Sites 

(Determine impairment) 

Impaired Condition / ' Not Impaired 

+ + Diagnose Cause of 

Impairment 

+ Implement Control 

No Action Required 

Continued Monitoring 

Recommended 

Fig. 3: Implementation of biological criteria requires the initial selection of reference sites and characterization of resident aquatic communities inhabiting those sites to establish 

the reference condition and biological criteria. After criteria 

development, impacted sites are evaluated using the same 

biosurvey procedures to assess resident biota. If impairment 

is found, diagnosis of cause will lead to the implementation 

of a control. Continued monitoring should accompany con· 

trol implementation to determine the effectiveness of intervention. Monitoring is also recommended where no impairment is found to ensure that the surface water maintains 

or improves in quality. 
The next step Is establishing the reference condition for the surface water being tested. This reference may be site specific or regional but must 

establish the unimpaired baseline for comparison 

(see Chapter 5, The Reference Condition). Once 

reference sites are selected, the biological integrity 

of the site must be evaluated using carefully chosen 

biological surveys. A quality biological survey will include multiple community components and may be 

measured using a variety of metrics (see Chapter 6, 

The Biological Survey). Establishing the reference 

condition and conducting biological surveys at the 

reference locations provide the necessary information for establishing the biological criteria. 

To apply biological criteria, impacted surface 

waters with comparable habitat characteristics are 

evaluated using the same procedures as those used 

to establish the criteria. The biological survey must 

support standardized sampling methods and statistical protocols that are sensitive enough to identify 

biologically relevant differences between established criteria and the community under evaluation. 

Resulting data are compared through hypothesis 

testing to determine impairment (see Chapter 7, 

Hypothesis Testing). 

When water quality impairments are detected 

using biological criteria, they can only be applied in 

a regulatory setting if the cause for impairment can 

be identified. Diagnosis is Iterative and investigative 

(see Chapter 7, Diagnosis). States must then determine appropriate actions to implement controls. 

Monitoring should remain a part of the biological 

criteria program whether impairments are found or 

not. If an impairment exists, monitoring provides a 

mechanism to determine if the control effort (intervention) is resulting In improved water quality. If 

there Is no Impairment, monitoring ensures the 

water quality is maintained and documents any improvements. When improvements in water quality 

are detected through monitoring programs two actions are recommended. When reference condition 

waters improve, biological criteria values should be 

recalculated to reflect this higher level of integrity. 

When impaired surface waters improve, states 

should reclassify those waters to reflect a refined 

designated use with a higher level of biological integrity. This provides a mechanism for progressive 

water quality improvement. 

Chapter S: The Conceptual Framework 

19 

Integrating Biological 

Criteria Into Surface Water 

Management 

I ntegrating biological criteria into existing water 

quality programs will help to assess use attainment/nonattainment, improve problem discovery in specific waterbodies, and characterize 

overall water resource condition within a region. 

Ideally, biological criteria function in an iterative manner. New biosurvey information can be used to refine 

use classes. Refined use classes will help support 

criteria development and improve the value of data 

collected in biosurveys. 

Implementing Biological 

Criteria 

As biological survey data are collected, these 

data will increasingly support current use of 

biomonitoring data to identify water quality 

problems, assess their severity, and set planning 

and management priorities for remediation. Monitoring data and biological criteria should be used at the 

outset to help make regulatory decisions, develop 

appropriate controls, and evaluate the effectiveness 

of controls once they are implemented. 

The value of incorporating biological survey information in regulatory programs is Illustrated by 

evaluations conducted by North Carolina. In 

21 

-

To integrate biological criteria into water quality 

programs, states must carefully determine where and 

how data are collected to assess the biological Integrity 

of surface waters. 

response to amendments of the Federal Water Pollution Control Act requiring secondary effluent limits 

for all wastewater treatment plants, North Carolina 

became embroiled in a debate over whether meeting secondary effluent limits (at considerable cost) 

would result in better water quality. North Carolina 

chose to test the effectiveness of additional treatment by conducting seven chemical and biological 

surveys before and after facility upgrades (North 
Blo/og/csl Criteria: National Program Guidance 

Carolina DNRCD 1984). Study results Indicated that 

moderate to substantial in-stream improvements 

were observed at six of seven facilities. Biological 

surveys were used as an efficient, cost-effective 

monitoring tool for assessing in-stream Improvements after facility modification. North Carolina has 

also conducted comparative studies of benthic macrolnvertebrate surveys and chemical-specific and 

whole-effluent evaluations to assess sensitivities of 

these measures for detecting Impairments 

(Eagleson et al. 1990). 

Narrative biological criteria provide a scientific 

framework for evaluating biosurvey, bioassessment, 

and biomonitoring data collected in most States. Initial application of narrative biological criteria may require only an evaluation of current work. States can 

use available data to define variables for choosing 

reference sites, selecting appropriate biological surveys, and assessing the response of local biota to a 

variety of Impacts. States should also consider the 

decision criteria that will be used for determining appropriate State action when impairment is found. 

Recent efforts by several States to develop 

biological criteria for freshwater streams provide excellent examples for how biological criteria can be 

Integrated into water quality programs. Some of this 

work ls described in the National Workshop on Instream Biological Monitoring and Criteria proceedings which recommended that "the concept of 

biological sampling should be integrated into the full 

spectrum of State and Federal surface water 

programs• (U.S. EPA 1987b). States are actively 

developing biological assessment and criteria 

programs; several have programs in place. 

Biological Criteria in State 

Programs 

Biological criteria are used within water 

programs to refine use designations, establish 

criteria for determining use attainmenVnonattainment, evaluate effectiveness of current water 

programs, and detect and characterize previously 

unknown impairments. Twenty States are currently 

using some form of standardized ambient biological 

assessments to determine the status of biota within 

State waters. Levels of effort vary from bioassessment studies to fully developed biological criteria 

programs. 

22 

Fifteen States are developing aspects of 

biological assessments that will support future 

development of biological criteria. Colorado, Illinois, 

Iowa, Kentucky, Massachusetts, Tennessee, and 

Virginia conduct biological monitoring to evaluate 

biological conditions, but are not developing biological criteria. Kansas is considering using a community metric for water resource assessment. 

Arizona Is planning to refine ecoreglons for the 

State. Delaware, Minnesota, Texas, and Wisconsin 

are developing sampling and evaluation methods to 

apply to future biological criteria programs. New 

York is proposing to use biological criteria for sitespecific evaluations of water quality impairment. 

Nebraska and Vermont use Informal biological 

criteria to support existing aquatic life narratives in 

their water quality standards and other regulations. 

Vermont recently passed a law requiring that 

biological criteria be used to regulate through permitting the indirect discharge of sanitary effluents. 

Florida incorporated a specific biological 

criterion into State standards for invertebrate 

species diversity. Species diversity within a waterbody, as measured by a Shannon diversity index, 

may not fall below 75 percent of reference values. 

This criterion has been used in enforcement cases 

to obtain injunctions and monetary settlements. 

Florida's approach is very specific and limits alternative applications. 

Four States-Arkansas, North Carolina, Maine, 

and Ohio-are currently using biological criteria to 

define aquatic life use classifications and enforce 

water quality standards. These states have made 

biological criteria an integral part of comprehensive 

water quality programs. 

• Arkansas rewrote its aquatic life use classifications for each of the State's ecoregions. This has allowed many cities to design wastewater treatment 

plants to meet realistic attainable dissolved oxygen 

conditions as determined by the new criteria. 

• North Carolina developed biological criteria to 

assess impairment to aquatic life uses written as narratives in the State water quality standards. Biological data and criteria are used extensively to identify 

waters of special concern or those with exceptional 

water quality. In addition to the High Quality Waters 

(HOW) and Outstanding Resource Waters (ORW) 

designations, Nutrient Sensitive Waters (NSW) at 

risk for eutrophlcation are assessed using biological 
criteria. Although specific biological measures are 

not In the regulations, strengthened use of biological 

monitoring data to assess water quality is being 

proposed for incorporation in North Carolina's water 

quality standards. 

• Maine has enacted a revised Water Quality 

Classification Law specifically designed to facilitate 

the use of biological assessments. Each of four 

water classes contains descriptive aquatic life conditions necessary to attain that class. Based on a 

statewide database of macroinvertebrate samples 

collected above and below outfalls, Maine is now 

developing a set of dichotomous keys that serve as 

the biological criteria. Maine's program is not expected to have a significant role In permitting, but will 

be used to assess the degree of protection afforded 

by effluent limitations. 

• Ohio has instituted the most extensive use of 

biological criteria for defining use classifications and 

assessing water quality. Biological criteria were 

developed for Ohio rivers and streams using an 

ecoregional reference site approach. Within each of 

the State's five ecoreglons, criteria for three biological Indices (two for fish communities and one for 

macroinvertebrates) were derived. Ohio successfully 

uses biological criteria to demonstrate attainment of 

aquatic life uses and discover previously unknown or 

unidentified environmental degradation (e.g., twice 

as many impaired waters were discovered using 

biological criteria and water chemistry together than 

were found using chemistry alone). The upgraded 

use designations based on biological criteria were 

upheld in Ohio courts and the Ohio EPA successfully 

proposed their biological criteria for inclusion in the 

State water quality standards regulations. 

States and EPA have learned a great deal about 

the effectiveness of integrated biological assessments through the development of biological criteria 

for freshwater streams. This information is particularly valuable In providing guidance on developing biological criteria for other surface water types. 

As previously discussed, EPA plans to produce supporting technical guidance for biological criteria 

development in streams and other surface waters. 

Production of these guidance documents will be 

contingent on technical progress made on each sur23 

Chapter 4: Integrating Blolog/cal Criteria 

face water type by researchers in EPA, States and 

the academic community. 

EPA will also be developing outreach workshops to provide technical assistance to Regions 

and States working toward the Implementation of 

biological criteria programs in State water quality 

management programs. In the Interim, States 

should use the technical guidance currently available In the Technical Support Manual(s): Waterbody 

Surveys and Assessments for Conducting Use Attainability Analysis (U.S. EPA 1983b, 1984a,b). 

During the next triennium, State effort will be 

focused on developing narrative biological criteria. 

Full implementation and Integration of biological 

criteria will require several years. Using available 

guidance, States can complement the adoption of 

narrative criteria by developing implementation 

plans that include: 

1. Defining program objectives, developing 

research protocols, and setting priorities; 

2. Determining the process for establishing 

reference conditions, which Includes 

developing a process to evaluate habitat 

characteristics; 

3. Establishing biological survey protocols that 

Include justifications for surface water 

classifications and selected aquatic 

community components to be evaluated; 

and 

4. Developing a formal document describing 

the research design, quality assurance and 

quality control protocols, and required 

training for staff. 

Whether a State begins with narrative biological 

criteria or moves to fully implement numeric criteria, 

the shift of the water quality program focus from 

source control to resource management represents 

a natural progression In the evolution from the technology-based to water quality-based approaches In 

water quality management. The addition of a 

biological perspective allows water quality programs 

to more directly address the objectives of the Clean 

Water Act and to place their efforts in a context that 

is more meaningful to the public. 
Biological Criteria: Nallonal Program Guidance 

Future Directions 

Biological criteria now focus on resident aquatic 

communities in surface waters. They have the 

potential to expand in scope toward greater ecological integration. Ecological criteria may encompass 

the ambient aquatic communities in surface waters, 

wildlife species that use the same aquatic resources, and the aquatic community inhabiting the 

gravel and sediments underlying the surface waters 

and adjacent land (hyporheic zone); specific criteria 

may apply to physical habitat. These areas may represent only a few possible options for biological 

criteria in the future. 

Many wildlife species depend on aquatic resources. If aquatic population levels decrease or if the 

distribution of species changes, food sources may 

be sufficiently altered to cause problems for wildlife 

species using aquatic resources. Habitat degradation that impairs aquatic species will often impact 

important wildlife habitat as well. These kinds of impairments are likely to be detected using biological 

criteria as currently formulated. In some cases, 

however, uptake of contaminants by resident 

aquatic organisms may not result in altered structure and function of the aquatic community. These 

impacts may go undetected by biological criteria, 

but could result in wildlife impairments because of 

bioaccumulation. Future expansion of biological 

criteria to include wildlife species that depend on 

aquatic resources could provide a more integrative 

ecosystem approach. 

Rivers may have a subsurface flood plain extending as far as two kilometers from the river channel. Preliminary mass transport calculations made 

in the Flathead River basin in Montana indicate that 

nutrients discharged from this subsurface flood 

plain may be crucial to biotic productivity in the river 

channel (Stanford and Ward 1988). This is an unexplored dimension in the ecology of gravel river beds 

and potentially in other surface waters. 

As discussed in Chapter 1, physical integrity is a 

necessary condition for biological integrity. Establishing the reference condition for biological criteria 

requires evaluation of habitat. The rapid bioassessment protocol provides a good example of the importance of habitat for interpreting biological 

assessments (Plafkin et al. 1989). However, it may 

be useful to more fully integrate habitat characteristics into the regulatory process by establishing 

criteria based on the necessary physical structure of 

habitats to support ecological integrity. 

24 
Part II 

The Implementation 

Process 
Blologlcal Criteria: National Program Guidance 

The implementation of biological criteria requires: (1) selection of unimpaired 

(minimal impact) surface waters to use as the reference condition for each designated use, (2) measurement of the structure and function of aquatic communities in 

reference surface waters to establish biological criteria, and (3) establishment of a 

protocol to compare the biological criteria to biota in impacted waters to determine 

whether impairment has occurred. These elements serve as an interactive network 

that is particularly important during early development of biological criteria 

where rapid acaimulation of information is effective for refining both designated 

uses and developing biological criteria values. The following chapters describe 

these three essential elements. 

26 
-

The Reference Condition 

A key step in developing values for supporting narrative and creating numeric biological criteria is to establish reference 

conditions; it is an essential feature of environmental 

impact evaluations (Green 1979}. Reference conditions are critical for environmental assessments because standard experimental controls are rarely 

available. For most surface waters, baseline data 

were not collected prior to an Impact, thus impairment must be inferred from differences between the 

impact site and established references. Reference 

. conditions describe the characteristics of waterbody 

segments least Impaired by human activities and are 

used to define attainable biological or habitat conditions. 

Wide variability among natural surface waters 

across the country .resulting from climatic, landform, 

and other geographic differences prevents the 

development of nationwide reference conditions. 

Most States are also too heterogeneous for single 

reference conditions. Thus, each State, and when 

appropriate, groups of States, will be responsible for 

selecting and evaluating reference waters within the 

State to establish biological criteria for a given surface water type or category of designated use. At 

least seven methods for estimating attainable conditions for streams have been Identified (Hughes et al. 

1986). Many of these can apply to other surface 

waters. References may be established by defining 

models of attainable conditions based on historical 

data or unimpaired habitat (e.g., streams In old 

growth forest). The reference condition established 

as before-after comparisons or concurrent mea27 

Reference conditions should be established by 

measuring resident biota In unimpaired ~urface waters. 

sures of the reference water and Impact sites can be 

based on empirical data (Hall et al. 1989). 

Currently, two principal approaches are used for 

establishing the reference condition. A State may 

opt to (1) Identify site-specific reference sites for 

each evaluation of impact or (2) select ecologically 

similar regional reference sites for comparison with 

impacted sites within the same region. Both approaches depend on evaluations of habitats to ensure that waters with similar habitats are compared. 

The designation of discrete habitat types Is more 

fully developed for streams and rivers. Development 

of habitat types for lakes, wetlands, and estuaries is 

ongoing. 
Blolog/ca/ Criteria: National Program Guidance 

Site-Specific Reference 

Condition 

A site-specific reference condition, frequently 

used to evaluate the impacts from a point discharge, 

is best for surface waters with a strong directional 

flow such as In streams and rivers (the upstreamdownstream approach). However, it can also be 

used for other surface waters where gradients in 

contaminant concentration occur based on 

proximity to a source (the near field-far field approach). Establishment of a site-specific reference 

condition requires the availability of comparable 

habitat within the same waterbody in both the reference location and the impacted area. 

A site-specific reference condition is difficult to 

establish if (1) diffuse nonpoint source pollution contaminates most of the water body; (2) modifications 

to the channel, shoreline, or bottom substrate are 

extensive; (3) point sources occur at multiple locations on the waterbody; or (4) habitat characteristics 

differ significantly between possible reference locations and the impact site (Hughes et al. 1986; Piafkin et al. 1989). In these cases, slte·specific 

reference conditions could result in underestimates 

of Impairment. Despite limitations, the use of sitespecific reference conditions Is often the method of 

choice for point source discharges and certain 

waterbodies, particularly when the relative impairments from different local impacts need to be determined. 

The Upstream-Downstream 

Reference Condition 

The upstream-downstream reference condition 

is best applied to streams and rivers where the 

habitat characteristics of the waterbody above the 

point of discharge are similar to the habitat characteristics of the stream below the point of discharge. 

One standard procedure is to characterize the biotic 

condition just above the discharge point (accounting 

for possible upstream circulation) to establish the 

reference condition. The condition below the discharge is also measured at several sites. If significant differences are found between these 

measures, impairment of the biota from the discharge is indicated. Since measurements of resident biota taken in any two sites are expected to 

differ because of natural variation, more than one 

28 

biological assessment for both upstream and 

downstream sites is often needed to be confident In 

conclusions drawn from these data (Green, 1979). 

However, as more data are collected by a State, and 

particularly If regional characteristics of the waterbodies are Incorporated, the basis for determining 

Impairment from site-specific upstream-downstream 

assessments may require fewer Individual samples. 

The same measures made below the "recovery 

zone• downstream from the discharge will help 

define where recovery occurs. 

The upstream-downstream reference condition 

should be used with discretion since the reference 

condition may be impaired from Impacts upstream 

from the point source of interest. In these cases it is 

Important to discriminate between Individual point 

source impact versus overall impairment of the system. When overall impairment occurs, the resident 

biota may be sufficiently impaired to make It Impossible to detect the effect of the target point source 

discharger. 

The approach can be cost effective when one 

biological assessment of the upstream reference 

condition adequately reflects the attainable condition of the impacted site. However, routine comparisons may require assessments of several 

upstream sites to adequately describe the natural 

variability of reference biota. Even so, measuring a 

series of site-specific references will likely continue 

to be the method of choice for certain point source 

discharges, especially where the relative Impairments from different local impacts need to be determined. 

The Near Field-Far Field Reference 

Condition 

The near field-far field reference condition Is effective for establishing a reference condition In surface waters other than rivers and streams and is 

particularly applicable for unique waterbodies (e.g., 

estuaries such as Puget Sound may not have comparable estuaries for comparison). To apply this 

method, two variables are measured (1) habitat 

characteristics, and (2) gradient of impairment. For 

reference waters to be Identified within the same 

waterbody, sufficient size Is necessary to separate 

the reference from the impact area so that a 

gradient of Impact exists. At the same time, habitat 

characteristics must be comparable. 
Although not fully developed, this approach may 

provide an effective way to establish biological 

criteria for estuaries, large lakes, or wetlands. For 

example, estuarine habitats could be defined and 

possible reference waters identified using physical 

and chemical variables like those selected by the 

Chesapeake Bay Program (U.S. EPA 1987a, e.g., 

substrate type, salinity, pH) to establish comparable 

subhabitats in an estuary. To determine those areas 

least impaired, a "mussel watch" program like that 

used in Narragansett Bay (i.e., captive mussels are 

used as indicators of contamination, (Phelps 1988)) 

could establish impairment gradients. These two 

measures, when combined, could form the basis for 

selecting specific habitat types in areas of least impairment to establish the reference condition. 

Regional Reference 

Conditions 

Some of the limitations of site-specific reference 

conditions can be overcome by using regional reference conditions that are based on the assumption 

that surface waters integrate the character of the 

land they drain. Waterbodies within the same watershed in the same region should be more similar to 

each other than to those within watersheds in different regions. Based on these assumptions, a distribution of aquatic regions can be developed based 

on ecological features that directly or indirectly relate to water quality and quantity, such as soil type, 

vegetation (land cover), land-surface form, climate, 

and land use. Maps that incorporate several of 

these features will provide a general purpose broad 

scale ecoregional framework (Gallant et al. 1989). 

Regions of ecological similarity are based on 

hydrologic, climatic, geologic, or other relevant 

geographic variables that influence the nature of 

biota in surface waters. To establish a regional reference condition, surface waters of similar habitat 

type are identified in definable ecological regions. 

The biological integrity of these reference waters is 

determined to establish the reference condition and 

develop biological criteria. These criteria are then 

used to assess impacted surface waters in the 

same watershed or region. There are two forms of 

regional reference conditions: (1) paired watersheds and (2) ecoregions. 

29 

Chapter 5: The Refenmc#J Condition 

Paired Watershed Reference 

Conditions 

Paired watershed reference conditions are established to evaluate impaired waterbodies, often 

Impacted by multiple sources. When the majority of 

a waterbody is impaired, the upstream-downstream 

or near field-far field reference condition does not 

provide an adequate representation of the unimpaired condition of aquatic communities for the 

waterbody. Paired watershed reference conditions 

are established by identifying unimpaired surface 

waters within the same or very similar local watershed that Is of comparable type and habitat. Variables to consider when selecting the watershed 

reference condition include absence of human disturbance, waterbody size and other physical characteristics, surrounding vegetation, and others as 

described in the "Regional Reference Site Selection• feature. 

This method has been successfully applied 

(e.g., Hughes 1985) and is an approach used in 

Rapid Bioassessment Protocols (Plafkin et al. 

1989). State use of this approach results in good 

reference conditions that can be used immediately 

in current programs. This approach has the added 

benefit of promoting the development of a database 

on high quality waters in the State that could form 

the foundation for establishing larger regional references (e.g., ecoregions.) 

Ecoregional Reference Conditions 

Reference conditions can also be developed on 

a larger scale. For these references, waterbodies of 

similar type are identified in regions of ecological 

similarity. To establish a regional reference condition, a set of surface waters of similar habitat type 

are identified in each ecological region. These sites 

must represent similar habitat type and be representative of the region. As with other reference conditions, the biological integrity of selected reference 

waters is determined to establish the reference. 

Biological criteria can then be developed and used 

to assess impacted surface waters in the same 

region. Before reference conditions may be established, regions of ecological similarity must be 

defined. 
Blolo(lk:al Criteria: National Program Guidance 

Regional Reference Site 

Selection 

To determine specific regional reference sites 

for streams, candidate watersheds are selected 

from the appropriate maps and evaluated to 

determine if they are typical for the region. An 

evaluation of level of human disturbance is made 

and a number of relatively undisturbed reference 

sites are selected from the candidate sites. 

Generally. watersheds are chosen as regional reference sites when they fall entirely within typical 

areas of the region. Candidate sites are then 

selected by aerial and ground surveys. Identification of candidate sites is based on: (1) absence 

of human disturbance, (2) stream size, (3) type 

of stream channel, (4) location within a natural or 

political refuge, and (5) historicai records of resident biota and possible migration barriers. 

Final selection of reference sites depends on 

a determination of minimal disturbance derived 

from habitat evaluation made during site visits. 

For example, indicators of good quality streams in 

forested ecoregions include: (1) extensive, old, 

natural riparian vegetation; (2) relatively high heterogeneity in channel width and depth; (3) abundant large woody debris, coarse bottom substrate, or extensive aquatic or overhanging vegetation; (4) relatively high or constant discharge; 

(5) relatively clear waters with natural color and 

odor; (6) abundant diatom, insect, and fish assemblages; and (7) the presence of piscivorous 

birds and mammals. 

One frequently used method Is described by 

Omernik (1987) who combined maps of land-surface form, soil, potential natural vegetation, and 

land use within the conterminous United States to 

generate a map of aquatic ecoregions for the 

country. He also developed more detailed regional 

maps. The ecoreglons defined by Omernik have 

been evaluated for streams and small rivers in 

Arkansas (Rohm et al. 1987), Ohio (Larsen et al. 

1986; Whittier et al. 1987), Oregon (Whittier et al. 

1988), Colorado (Gallant et al. 1989), and Wisconsin (Lyons 1989) and for lakes in Minnesota (Heiskary et al. 1987). State ecoregion maps were 

30 

developed for Colorado (Gallant et al. 1989) and 

Oregon (Clarke et al. mss). Maps for the national 

ecoregions and six multi-state maps of more 

detailed ecoregions are available from the U.S. EPA 

Environmental Research Laboratory, Corvallis, 

Oregon. 

Ecoregions such as those defined by Omernik 

(1987) provide only a first step in establishing 

regional reference sites for development of the reference condition. Field site evaluation Is required to 

account for the Inherent variability within each 

ecoregion. A general method for selecting reference 

sites for streams has been described (Hughes et al. 

1986). These are the same variables used for comparable watershed reference site selection. 

Regional and on-site evaluations of biological factors help determine specific sites that best represent 

typical but unimpaired surface water habitats within 

the region. Details on this approach for streams is 

described in the "Regional Reference Site Selection" feature. To date, the regional approach has 

been tested on streams, rivers, and lakes. The 

method appears applicable for assessing other inland ecosystems. To apply this approach to wetlands and estuaries will require adc;litlonal 

evaluation based on the relevant ecological features 

of these ecosystems (e.g. Brooks and Hughes, 

1988). 

Ideally, ecoregional reference sites should be 

as little disturbed as possible, yet represent waterbodies for which they are to serve as reference 

waters. These sites may serve as references for a 

large number of similar waterbodies (e.g., several 

reference streams may be used to define the reference condition for numerous physically separate 

streams if the reference streams contain the same 

range of stream morphology, substrate, and flow of 

the other streams within the same ecological 

region). 

An important benefit of a regional reference system is the establishment of a baseline condition for 

the least Impacted surface waters within the 

dominant land use pattern of the region. In many 

areas a return to pristine, or presettlement, conditions is impossible, and goals for waterbodies In extensively developed regions could reflect this. 

Regional reference sites based on the least Impacted sites within a region will help water quality 

programs restore and protect the environment in a 

way that Is ecologically feasible. 
This approach must be used with caution for two 

reasons. First, in many urban, industrial, or heavily 

developed agricultural regions, even the least impacted sites are seriously degraded. Basing standards or criteria on such sites will set standards too 

low if these high levels of environmental degradation are considered acceptable or adequate. In such 

degraded regions, alternative sources for the 

regional reference may be needed (e.g., measures 

taken from the same region in a less developed 

neighboring State or historical records from the 

region before serious impact occurred). Second, in 

some regions the minimally-impacted sites are not 

typical of most sites in the region and may have 

remained unimpaired precisely because they are 

unique. These two considerations emphasize the 

need to select reference sites very carefully, based 

on solid quantitative data interpreted by professionals familiar with the biota of the region. 

Each State, or groups of States, can select a 

series of regional reference sites that represent the 

attainable conditions for each region. Once biological criteria are established using this approach, the 

cost for evaluating local impairments is often lower 

than a series of measures of site-specific reference 

sites. Using paired watershed reference conditions 

immediately in regulatory programs will provide the 

added benefit of building a database for the 

development of regions of ecological similarity. 

Chapter 5: The Reference Condition 

31 
I 
-

The Biological Survey 

A critical element of biological criteria is the 

characterization of biological communities 

. inhabiting surface waters. Use of biological 

data is not new; biological information has been used 

to assess impacts from pollution since the 1890s 

(Forbes 1928), and most States currently incorporate biological information in their decisions about 

the quality of surface waters. However, biological information can be obtained through a variety of 

methods, some of which are more effective than 

others for characterizing resident aquatic biota. 

Biological criteria are developed using biological surveys; these provide the only direct method for 

measuring the structure and function of an aquatic 

community. 

Different subhabltat within the same surface water wlll 

contain unique aquatic community components. In 

fast-flowing stream segments species such as (1) black 

fly larva; (2) brook trout; (3) water penny; (4) crane fly 

larva; and (5) water moss occur. 

33 

However, In slow-flowing stream segments, species 

like (1) water strider; (2) smallmouth bass; (3) crayfish; 

and (4) flngemall clams are abundant. 

Biological survey study design is of critical importance to criteria development. The design must 

be scientifically rigorous to provide the basis for 

legal action, and be biologically relevant to detect 

problems of regulatory concern. Since it is not financially or technically feasible to evaluate all organisms in an entire ecosystem at all times, careful 

selection of community components, the time and 

place chosen for assessments, data gathering 

methods used, and the consistency with which 

these variables are applied will determine the success of the biological criteria program. Biological 

surveys must therefore be carefully planned to meet 

scientific and legal requirements, maximize information, and minimize cost. 
Biological Criteria: Nations/ Program Guidance 

Blologlcal surveys can range from collecting 

samples of a single species to comprehensive 

evaluations of an entire ecosystem. The first approach Is difficult to Interpret for community assessment; the second approach Is expensive and 

Impractical. A balance between these extremes can 

meet program needs. Current approaches range 

between detailed ecological surveys, biosurveys of 

targeted community components, and biological indicators (e.g., keystone species). Each of these 

biosurveys has advantages and limitations. Additional discussion will be provided in technical 

guidance under development. 

No single type of approach to biological surveys 

is always best. Many factors affect the value of the 

approach, including seasonal variation, waterbody 

size, physical boundaries, and other natural characteristics. Pilot testing alternative approaches In 

State waters may be the best way to determine the 

sensitivity of specific methods for evaluating biological integrity of local waters. Due to the number of alternatives available and the diversity of ecological 

systems, individuals responsible for research 

design should be experienced biologists with expertrse in the local and regional ecology of target surface waters. States should develop a data 

management program that includes data analysis 

and evaluation and standard operating procedures 

as part of a Quality Assurance Progral'T'! Plan. 

When developing study designs for biological 

criteria, two key elements to consider include (1) 

selecting aquatic community components that will 

best represent the biological integrity of State surface waters and (2) designing data collection 

protocols to ensure the best representation of the 

aquatic community. Technical guidance currently 

available to aid the development of study design include: Water Quality Standards Handbook (U.S. 

EPA 1983a), Technical Support Manual: Waterbody 

Surveys and Assessments for Conducting Use Attainability Analyses (U.S. EPA 1983b); Technical 

Support Manual: Waterbody Surveys and Assessments for Conducting Use Attainability Analyses, 

Volume II: Estuarine Systems (U.S. EPA 1984a); 

and Technical Support Manual: Waterbody Surveys 

and Assessments for Conducting Use Attainability 

Analyses, Volume Ill: Lake Systems (U.S. EPA 

1984b). Future technical guidance will build on 

these documents and provide specific guidance for 

biological criteria development. 

34 

Selecting Aquatic 

Community Components 

Aquatic communities contain a variety of 

species that represent different trophic levels, 

taxonomic groups, functional characteristics, and 

tolerance ranges. Careful selection of target 

taxonomic groups can provide a balanced assessment that Is sufficiently broad to describe the structural and functional condition of an aquatic 

ecosystem, yet be sufficiently practical to use on a 

daily basis (Plafkln et al. 1989; Lenat 1988). When 

selecting community components to include In a 

biological assessment, primary emphasis should go 

toward Including species or taxa that (1) serve as effective Indicators of high biological Integrity (I.e., 

those likely to live In unimpaired waters), {2) represent a range of pollution tolerances, (3) provide predictable, repeatable results, and (4) can be readily 

Identified by trained State personnel. 

Fish, macroinvertebrates, algae, and zooplankton are most commonly used in current bloassessment programs, The taxonomic groups chosen will 

vary depending on the type of aquatic ecosystem 

being assessed and the type of expected Impairment. For example, benthlc macrolnvertebrate and 

fish communities are taxonomic groups often 

chosen for flowing fresh water. Macroinvertebrates 

and fish both provide valuable ecological information. while fish correspond tq the. regulatory and 

public perceptions of water quality and reflect 

cumulative environmental stress over longer time 

frames. Plants are often used In wetlands, and 

algae are useful in lakes and estuaries to assess 

eutrophlcation. In marine systems, benthlc macroinvertebrates and submerged aquatic vegetation may 

provide key community components. Amphipods, 

for example, dominate many aquatic communities 

and are more sensitive than other invertebrates i 

such as polychaetes and molluscs to a wide variety 

of pollutants Including hydrocarbons and heavy metals (Reich and Hart 1979; J.D. Thomas, pers. 

comm.). 

It is beneficial to supplement standard groups 

with additional community components to meet 

specific goals, objectives, and resources of the assessment program. Biological surveys that use two 

or three taxonomic groups (e.g., fish, macroinvertebrates, algae) and, where appropriate, Include different trophic levels within each group (e.g., 

primary, secondary, and tertiary consumers) will 
provide a more realistic evaluation of system 

biological integrity. This is analogous to using 

species from two or more taxonomic groups in 

bioassays. Impairments that are difficult to detect 

because of the temporal or spatial habits or the pollution tolerances of one group may be revealed 

through impairments in different species or assemblages (Ohio EPA 1988a). 

Selection of aquatic community components 

that show different sensitivities and responses to 

the same perturbation will aid in identifying the nature of a problem. Available data on the ecological 

function, distribution, and abundance of species in a 

given habitat will help determine the most appropriate target species or taxa for biological surveys in the habitat. The selection of community 

components should also depend on the ability of the 

organisms to be accurately identified by trained 

State personnel. Attendant with the biological 

criteria program should be the development of identification keys for the organisms selected for study 

in the biological survey. 

Biological Survey Design 

Biological surveys that measure the structure 

and function of aquatic communities will provide the 

information needed for biological criteria development. Elements of community structure and function 

may be evaluated using a series of metrics. Structural metrics describe the composition of a community, such as the number of different species, 

relative abundance of specific species, and number 

and relative abundance of tolerant and intolerant 

species. Functional metrics describe the ecological 

processes of the community. These may include 

measures such as community photosynthesis or 

respiration. Function may also be estimated from 

the proportions of various feeding groups (e.g., omnivores, herbivores, and insectivores, or shredders, 

collectors, and grazers). Biological surveys can 

offer variety and flexibility in application. Indices currently available are primarily for freshwater streams. 

However, the approach has been used for lakes and 

can be developed for estuaries and wetlands. 

Selecting the metric 

Several methods are currently available for 

measuring the relative structural and functional wellbeing of fish assemblages in freshwater streams, 

35 

I 

Chapter 6: The Biologlcal Survey ' 

such as the Index of Biotic Integrity (IBI); Karr 1981; 

Karr et al. 1986; Miller et al. 1988) and the Index of 

Well-being (IWB; Gammon 1976, Gammon et al. 

1981). The IBI is one of the more widely used assessment methods. For additional detail, see the 

"Index of Biotic Integrity• feature. 

Index of Biotic Integrity 

The Index of Biotic Integrity (181) is commonly 

used for fish community analysis (Karr 1981). The 

original 181 was comprised of 12 metrics: 

• six metrics evaluate species richness and 

composition 

• number of species 

• number of darter species 

• number of sucker species 

• number of sunfish species 

,, • number of intolerant species ' 

• proportion of green sunfish 

• three metrics quantify trophic composition 

• proportion of omnivores 

• proportion of insectivorous cyprinids 

• proportion of piscivores 

• three metrics summarize fish abundance and 

condition information 

• number of individuals in sample 

• proportion of hybrids 

• proportion of individuals with disease 

Each metric is scored 1 (worst), 3, or 5 (best), 

depending on how the field data compare with an 

expected value obtained from reference sites. All 

12 metric values are then summed to provide an 

overall index value that represents relative integrity. The 181 was designed for midwestern 

streams; substitute metrics reflecting the same 

structural and functional characteristics have 

been created to accommodate regional variations 

In fish assemblages (Miller et al. 1988). 
Blolog/cal Criteria: National Program Guldanc8 

Several Indices that evaluate more than one 

community characteristic are also available for assessing stream macroinvertebrate populations. 

Taxa richness, EPT taxa (number of taxa of the Insect orders Ephemeroptera, Plecoptera, and Tricoptera), and species pollution tolerance values are a 

few of several components of these macroinvertebrate assessments. Example indices Include the 

Invertebrate Community Index (ICI; Ohio EPA, 

1988) and Hilsenhoff Biotic Index (HBI; Hilsenhoff, 

1987). 

Within these metrics specific Information on the 

pollution tolerances of different species within a system will help define the type of impacts occurring in 

a waterbody. Biological indicator groups (intolerant 

species, tolerant species, percent of diseased organisms) can be used for evaluating community 

biological Integrity If sufficient data have been collected to support conclusions drawn from the indicator data. In marine systems, for example, 

amphlpods have been used by a number of researchers as environmental indicators (Mcca·11 

1977; Botton 1979; Mearns and Word 1982). 

Sampling design 

Sampling design and statistical protocols are required to reduce sampling error and evaluate the 

natural variability of biological responses that are 

found in both laboratory and field data. High 

variability reduces the power of a statistical test to 

detect real impairments (Sokal and Rohlf, 1981). 

States may reduce variability by refining sampling 

techniques and protocol to decrease variability introduced during data collection, and increase the 

power of the evaluation by increasing the number of 

replications. Sampling techniques are refined, in 

part, by collecting a representative sample of resident biota from the same component of the aquatic 

community from the same habitat type in the same 

way at sites being compared. Data collection 

protocols should incorporate (1) spatial scales 

(where and how samples are collected) and (2) temporal scales (when data are collected) (Green, 

1979): 

• Spatial Scales refer to the wide variety of subhabitats that exist within any surface water 

habitat. To account for subhabitats, adequate 

sampling protocols require selecting (1) the 

location within a habitat where target groups 

36 

reside and (2) the method for collecting data on 

target groups. For example, if fish are sampled 

only from fast flowing riffles within stream A, but 

are sampled from slow flowing pools in stream 

B, the data will not be comparable. 

• Temporal Scales refer to aquatic community 

changes that occur over time because of diurnal 

and fife-cycle changes in organism behavior or 

development, and seasonal or annual changes 

in the environment. Many organisms go through 

seasonal life-cycle changes that dramatically 

affect their presence and abundance in the 

aquatic community. For example, macroinvertebrate data collected from stream A in March 

and stream B in May, would not be comparable 

because the emergence of insect adults after 

March would significantly alter the abundance 

of subadults found in stream B in May. Similar 

problems would occur if algae were collected in 

lake A during the dry season and lake B during 

the wet season. 

Field sampling protocols that produce quality 

assessments from a limited number of site visits 

greatly enhance the utility of the sampling technique. Rapid bioassessment protocols, recently 

developed for assessing streams, use standardized 

techniques to quickly gather physical, chemical, and 

biological quantitative data that can assess changes 

in biological integrity (Plafkin et al. 1989). Rapid 

bioassessment methods can be cost-effective 

biological assessment approaches when they have 

been verified with more comprehensive evaluations 

for the habitats and region where they are to be applied. 

Biological survey methods such as the IBI for 

fish and ICI for macroinvertebrates were developed 

in streams and rivers and have yet to be applied to 

many ecological regions. In addition, further research is needed to adapt the approach to lakes, 

wetlands, and estuaries, including the development 

of alternative structural or functional endpoints. For 

example, assessment methods for algae (e.g. 

measures of biomass, nuisance bloom frequency, 

community structure) have been used for lakes. Assessment metrics appropriate for developing 

biological criteria for lakes, large rivers, wetlands, 

and estuaries are being developed and tested so 

that a multi-metric approach can be effectively used 

for all surface waters. 
-

Hypothesis Testing: 

Biological Criteria and the 

Scientific Method 

'B iological criteria are applied in the standards 

program by testing hypotheses about the 

_ biological integrity of impacted surface 

waters. These hypotheses include the null 

hypothesis-the designated use of the waterbody is 

not impaired-and alternative hypotheses such as 

the designated use of the waterbody is impaired 

(more specific hypotheses can also be generated 

that predict the type(s) of impairment). Under these 

hypotheses specific predictions are generated concerning the kinds and numbers of organisms representing community structure and function expected 

or found in unimpaired habitats. The kinds and numbers of organisms surveyed in unimpaired waters 

are used to establish the biological criteria. To test 

the alternative hypotheses, data collection and 

analysis procedures are used to compare the criteria 

to comparable measures of community structure and 

function in impacted waters. 

Hypothesis Testing 

To detect differences of biological and regulatory concern between biological criteria and ambient 

biological integrity at a test site, it is important to establish the sensitivity of the evaluation. A 10 percent 

difference in condition is more difficult to detect than 

a 50 percent difference. For the experimental/survey design to be effective, the level of detection 

should be predetermined to establish sample size 

37 

Multiple Impacts in the same surface water such as 

discharges of effluent from point sources, leachate from 

landfills or dumps, and erosion from habitat degradation 

each contribute to impairment of the surface water. All 

impacts should be considered during the diagnosis 

process. 

for data collection (Sokal and Rohlf 1981). 

Knowledge of expected natural variation, experimental error, and the kinds of detectable differences 

that can be expected will help determine sample 
Blologlcal Criteria: National Program Guidance 

size and location. This forms the basis for defining 

data quality objectives, standardizing data collection 

procedures, and developing quality assurance/ 

quality control standards. 

Once data are collected and analyzed, they are 

used to test the hypotheses to determine if characteristics of the resident biota at a test site are significantly different from established criteria values 

for a comparable habitat. There are three possible 

outcomes: 

1. The use is Impaired when survey design and 

data analyses are sensitive enough to detect 

differences of regulatory Importance, and 

significant differences were detected. The 

next step Is to diagnose the cause(s) and 

source(s) of impairment. 

2. The biological criteria are met when survey 

design and data analyses are sensitive 

enough to detect differences of regulatory 

significance, but no differences were found. 

In this case, no action Is required by States 

based on these measures. However, other 

evidence may Indicate impairment (e.g., 

chemical criteria are violated; see below). 

3. The outcome Is Indeterminate when survey 

design and data analyses are not sensitive 

enough to detect differences of regulatory 

significance, and no differences were 

detected. If a State or Region determines 

that this Is occurring, the development of 

study design and evaluation for biological 

criteria was Incomplete. States must then 

determine whether they will accept the 

sensitivity of the survey or conduct 

additional surveys to increase the power of 

their analyses. If the sensitivity of the 

original survey Is accepted, the State should 

determine what magnitude of difference the 

survey Is capable of detecting. This will aid 

In re-evaluating research design and desired 

detection limits. An Indeterminate outcome 

may also occur If the test site and the 

reference conditions were not comparable. 

This variable may also require re-evaluation. 

As with all scientific studies, when implementing 

biological criteria, the purpose of hypothesis testing 

is to determine If the data support the conclusion 

that the null hypothesis is false (i.e., the designated 

38 

use Is not Impaired In a particular waterbody). 

Biological criteria cannot prove attainment. This 

reasoning provides the basis for emphasizing independent application of different assessment 

methods (e.g., chemical verses biological criteria). 

No type of criteria can •prove• attainment; each type 

of criteria can disprove attainment. 

Although this discussion Is limited to the null 

and one alternative hypothesis, It Is possible to 

generate multiple working hypotheses (Popper, 

1968) that promote the diagnosis of water quality 

problems when they exist. For example, if physical 

habitat limitations are believed to be causing impairment (e.g., sedimentation) one alternative 

hypothesis could specify the loss of community 

components sensitive to this Impact. Using multiple 

hypotheses can maximize the information gained 

from each study. See the Diagnosis section for additional discussion. 

Diagnosis 

When Impairment of the designated use is 

found using biological criteria, a diagnosis of probable cause of impairment is the next step for Implementation. Since biological criteria are primarily 

designed to detect water quality Impairment, 

problems are likely to be Identified without a known 

cause. Fortunately the process of evaluating test 

sites for biological Impairment provides significant 

information to aid in determining cause. 

During diagnostic evaluations, three main Impact categories should be considered: chemical, 

physical, and biological. To begin the diagnostic 

process two questions are posed: 

• What are the obvious causes of Impairment? 

• If no obvious causes are apparent, what 

possible causes do the biological data 

suggest? 

Obvious causes such as habitat degradation, 

point source discharges, or introduced species are 

often identified during the course of a normal field 

biological assessment. Blomonltorlng programs normally provide knowledge of potential sources of impact and characteristics of the habitat. As such, 

diagnosis is partly incorporated Into many existing 

State field-oriented bioassessment programs. If 

more than one Impact source is obvious, diagnosis 
will require determining which impact(s) is the cause 

of impairment or the extent to which each impact 

contributes to impairment. The nature of the biological impairment can guide evaluation (e.g., chemical 

contamination may lead to the loss of sensitive 

species, habitat degradation may result in loss of 

breeding habitat for certain species). 

Case studies illustrate the effectiveness of 

biological criteria in identifying Impairments and 

possible sources. For example, in Kansas three 

sites on Little Mill Creek were assessed using Rapid 

Bioassessment Protocols (Plafkin et al. 1989; see 

Fig. 4). Based on the results of a comparative 

analysis, habitats at the three sites were comparable and of high quality. Biological impairment, 

however, was identified at two of the three sites and 

directly related to proximity to a point source discharge from a sewage treatment plant. The severely 

impaired Site (STA 2) was located approximately 

100 meters downstream from the plant. The slightly 

impaired Site (STA 3) was located between one and 

two miles downstream from the plant. However, the 

unimpaired Site (STA 1 (R)) was approximately 150 

meters upstream from the plant (Plafkin et al. 1989). 

This simple example illustrates the basic principles 

of diagnosis. In this case the treatment plant appears responsible for impairment of the resident 

biota and the discharge needs to be evaluated. 

Chapter 7: Hypothesis Testing 

Based on the biological survey the results are clear. 

However, impairment in resident populations of 

macroinvertebrates probably would not have been 

recognized using more traditional methods. 

In Maine, a more complex problem arose when 

effluents from a textile plant met chemical-specific 

and effluent toxicity criteria, yet a biological survey 

of downstream biota revealed up to 80 percent 

reduction in invertebrate richness below plant outfalls. Although the source of Impairment seemed 

clear, the cause of impairment was more difficult to 

determine. By engaging in a diagnostic evaluation, 

Maine was able to determine that the discharge contained chemicals not regulated under current 

programs and that part of the toxicity effect was due 

to the sequential discharge of unique effluents 

(tested individually these effluents were not toxic; 

when exposure was in a particular sequence, 

toxicity occurred). Use of biological criteria resulted 

in the detection and diagnosis of this toxicity problem, which allowed Maine to develop workable alternative operating procedures for the textile industry 

to correct the problem (Courtemanch 1989, and 

pars. comm.). 

During diagnosis it is important to consider and 

discriminate among multiple sources of impairment. 

In a North Carolina stream (see Figure 5) four sites 

were evaluated using rapid bioassessment techniFigure 4.-Kansas: Benthlc Bloassessment of Little Mill Creek (Little Mill Creek = Site-Specific Reference) 

Relationship of Habitat and Bioassessment 

<II 30 u 

C> 20 

0 

0 iii 10 

10 20 30 

STA3 1 

40 50 60 70 80 90 100 

Habitat Quality(% of Reference) 

Fig. 4: Three stream segments sampled in a stream In Kansas using Rapid Bioassessment Protocols (Plafkin et al. 1989) revealed 

significant impairments at sites below a sewage treatment plant. 

39 
Blologlcal Criteria: National Program Guidance 

Figure 5.-The Relatlonshlp Between Habitat Quality and Benthic Community. Condition at the North Carolina 

Piiot Study Site. ' · 

100 

Qi' 

0 90 c: 

Cl> 

.... 

Cl> 80 -Cl> 

a: 70 -0 

0 ~ 60 -

c: 

.Q 50 -~ 

"O 

c: 40 

0 

() 30. a; 

0 

·ei 20 

.Q 

.Q 10 ID 

0 

0 10 20 30 40 50 60 

Partially 

Supporting 

70 

Supporting 

80 90 100 

Habitat Quality (% of Reference) 

Fig. 5: Distinguishing between point and nonpoint sources of impairment requires an evaluation of the nature and magnitude 

of different sites in a surface water. (Plafkin, et al. 1989) 

ques. An ecoregional reference site (R) established 

the highest level of biological Integrity for that 

stream type. Site (1), well upstream from a local 

town, was used as the upstream reference condition. Degraded conditions at Site (2) suggested nonpoint source problems and habitat degradation 

because of proximity to residential areas on the 

upstream edge of town. At Site (3) habitat alterations, nonpoint runoff, and point source discharges 

combined to severely degrade resident biota. At this 

site, sedimentation and toxicity from municipal 

sewage treatment effluent appeared responsible for 

a major portion of this degradation. Site (4), although several miles downstream from town, was 

still impaired despite significant improvement in 

habitat quality. This suggests that toxicity from 

upstream discharges may still be occurring (Barbour, 1990 pers. comm.). Using these kinds of comparisons, through a diagnostic procedure and by 

using available chemical and biological assessment 

tools, the relative effects of impacts can be determined so that solutions can be formulated to improve water quality. 

When point and nonpoint impact and physical 

habitat degradation occur simultaneously, diagnosis 

may require the combined use of biological, physical, and chemical evaluations to discriminate be40 

tween these impacts. For example, sedimentation of 

a stream caused by logging practices is likely to 

result in a decrease in species that require loose 

gravel for spawning but increase species naturally 

adapted to fine sediments. This shift in community 

components correlates well with the observed impact. However, if the impact is a point source discharge or nonpoint runoff of toxicants, both species 

types are likely to be impaired whether sedimentation occurs or not (although gravel breeding species 

can be expected to show greater impairment if 

sedimentation occurs). Part of the diagnostic 

process is derived from an understanding of organism sensitivities to different kinds of impacts and 

their habitat requirements. When habitat is good but 

water quality is poor, aquatic community components sensitive to toxicity will be impaired. However, If both habitat and water quality degrade, the 

resident community is likely to be composed of 

tolerant and opportunistic species. 

When an impaired use cannot be easily related 

to an obvious cause, the diagnostic process becomes investigative and iterative. The iterative diagnostic process as shown in Figure 6 may require 

additional time and resources to verify cause and 

source. Initially, potential sources of impact are 

identified and mapped to determine location relative 
Figure 6.-Dlagnostlc Process 

Establish Biological Criteria 

+ 

Conduct Field Assessment to Determine Impairment 

Yes /' No~ No Further t Action 

Evaluate Data to Determine 

Probable Cause 

t 

Generate Testable Hypotheses 

for Probable Cause 

+ ----~ Collect Data and 

Evaluate Results .... --------

No Apparent 

t 

Cause 

~ Obvious Cause 

t t 

Propose New Alternative Formulate Remedial 

Hypotheses and Collect · Action 

New Data 

Fig. 6: The diagnostic process is a stepwise process for 

determining the cause of impaired biological integrity in surface waters. It may require multiple hypotheses testing and 

more than one remedial plan. 

41 

Chapter 7: Hypothesis Testing 

to the area suffering from biological Impairment. An 

analysis of the physical, chemical, and biological 

characteristics of the study area will help identify the 

most likely sources and determine which data will 

be most valuable. Hypotheses that distinguish between possible causes of Impairment should be 

generated. Study design and appropriate data collection procedures need to be developed to test the 

hypotheses. The severity of the impairment, the difficulty of diagnosis, and the costs involved will 

determine how many iterative loops will be completed in the diagnostic process. 

Normally, diagnoses of biological impairment 

are relatively straightforward. States may use 

biological criteria as a method to confirm Impairment 

from a known source of Impact. However, the diagnostic process provides an effective way to identify 

unknown impacts and diagnose their cause so that 

corrective action can be devised and implemented. 

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Appe11dix A 

Common Questions and 

Their Answers 

Q. How will implementing biological criteria 

benefit State water quality programs? 

A. State water quality programs will benefit from 

biological criteria because they: 

a) directly assess impairments in ambient 

biota from adverse impacts on the 

environment; 

b) are defensible and quantifiable; 

c) document improvements in water quality 

resulting from agency action; 

d) reduce the likelihood of false positives (i.e., 

a conclusion that attainment is achieved 

when it is not); 

e) provide information on the integrity of 

biological systems that is compelling to the 

public. 

Q. How will biological criteria be used in a 

permit program? 

A. When permits are renewed, records from 

chemical analyses and biological assessments are 

used to determine if the permit has effectively 

prevented degradation and led to improvement. The 

purpose for this evaluation is to determine whether 

applicable water quality standards were achieved 

under the expiring permit and to decide if changes 

are needed. Biological surveys and criteria are particularly effective for determining the quality of 

waters subject to permitted discharges. Since 

biosurveys provide ongoing integrative evaluations 

of the biological integrity of resident biota, permit 

45 

writers can make informed decisions on whether to 

maintain or restrict permit limits. 

Q. What expertise and staff will be needed to 

implement a biological criteria program? 

A. Staff with sound knowledge of State aquatic 

biology and scientific protocol are needed to coordinate a biological criteria program. Actual field 

monitoring could be accomplished by summer-hire 

biologists led by permanent staff aquatic biologists. 

Most States employ aquatic biologists for monitoring trends or issuing site-specific permits. 

Q. Which management personnel should be 

involved in a biologically-based approach? 

A. Management personnel from each area 

within the standards and monitoring programs 

should be involved in this approach, including permit engineers, resource managers, and field personnel. 

Q. How much will this approach cost? 

A. The cost of developing biological criteria is a 

State-specific question depending upon many variables. However, States that have implemented a 

biological criteria program have found it to be cost 

effective (e.g., Ohio). Biological criteria provide an 

integrative assessment over time. Biota reflect multiple impacts. Testing for impairment of resident 

aquatic communities can actually require less 

monitoring than would be required to detect many 

impacts using more traditional methods (e.g., 

chemical testing for episodic events). 
Biological Criteria: National Program Guidance 

Q, What are some concerns of dischargers? 

A. Dischargers are concerned that bJ016glcal 

criteria will identify impairments that may be erroneously attributed to a discharger who Is not 

responsible. This Is a legitimate concern that the 

discharger and State must address with careful 

evaluations and diagnosis of cause of impairment. 

However, it Is particularly important to ensure that 

waters used for the reference condition are not already impaired as may occur when conducting 

site-specific upstream-downstream evaluations. Although a discharger may be contributing to surface 

water degradation, it may be hard to detect using 

biosurvey methods if the waterbody is also impaired 

from other sources. This can be evaluated by testing the possible toxicity of effluent-free reference 

waters on sensitive organisms. 

Dischargers are also concerned that current 

permit limits may become more stringent if it is 

determined that meeting chemical and whole-effluent permit limits are not sufficient to protect 

aquatic life from discharger activities. Alternative 

forms of regulation may be needed; these are not 

necessarily financially burdensome but could involve additional expense. 

Burdensome monitoring requirements are additional concerns. With new rapid bioassessment 

protocols available for streams, and under development for other surface waters, monitoring resident 

biota is becoming more straightforward. Since resident biota provide an integrative measure of environmental impacts over time, the need for 

continual biomonitoring is actually lower than 

chemical analyses and generally less expensive. 

Guidance is being developed to establish acceptable research protocols, quality assurance/quality 

control programs and training opportunities to ensure that adequate guidance is available. 

Q. What are the concerns of 

environmentalists? 

A. Environmentalists are concerned that biological criteria could be used to alter restrictions on dischargers if biosurvey data indicate attainment of a 

designated use even though chemical criteria 

and/or whole-effluent toxicity evaluations predict impairment. Evidence suggests that this occurs infrequently (e.g., in Ohio, 6 percent of 431 sites 

evaluated using chemical-specific criteria and 

biosurveys resulted in this disagreement). In those 

46 

cases where evidence suggests more than one conclusion, independent application applies. If biological criteria suggest impairment but chemicalspecific and/or whole-effluent toxicity implies attainment of the use, the cause for impairment of the 

biota is to be evaluated and, where appropriate, 

regulat~d. If whole effluent and/or chemical-specific 

criteria imply impairment but no impairment is found 

in resident biota, the whole-effluent and/or chemical-specific criteria provide the basis for regulation. 

Q. Do biological criteria have to be codified 

in State regulations? 

A. State water quality standards require three 

components: (1) designated uses, (2) protective 

criteria, and (3) an antidegradation clause. For 

criteria to be enforceable they must be codified in 

regulations. Codification could involve general narrative statements of biological criteria, numeric 

criteria, and/or criteria accompanied by specific testing procedures. Codifying general narratives 

provides the most flexibility-specific methods for 

data collection the least flexibility-for incorporating 

new data and improving data gathering methods as 

the biological criteria program develops. States 

should carefully consider how to codify these 

criteria. 

Q. How will biocriteria fit into the agency's 

method of implementing standards? 

A. Resident biota integrate multiple impacts 

over time and can detect impairment from known 

and unknown causes. Biocriteria can be used to 

verify improvement in water quality in response to 

regulatory efforts and detect continuing degradation 

of waters. They provide a framework for developing 

improved best management practices for nonpoint 

source impacts. Numeric criteria can provide effective monitoring criteria for inclusion in perrnits. 

Q. Who determines the values for biological 

criteria and decides whether a waterbody meets 

the criteria? 

The process of developing biological criteria, including refined use classes, narrative criteria, and 

numeric criteria, must include agency managers, 

staff biologists, and the pub I ic through public hearings and comment. Once criteria are established, 

determining attainment\nonattainment of a use re-
quires biological and statistical evaluation based c;m 

established protocols. Changes in the criteria would 

require the same steps as the initial criteria: technical modifications by biologists, goal clarification by 

agency managers, and public hearings. The key to 

criteria development and revision is a clear statement of measurable objectives. 

Q. What additional information is available 

on developing and using biological criteria? 

A. This program guidance document will be 

supplemented by the document Biological Criteria 

Development by States that includes case histories 

of State implementation of biological criteria as narratives, numerics, and some data procedures. The 

purpose for the document is to expand on material 

presented in Part I. The document will be available 

in October 1990. 

A general Biological Criteria Technical Reference Guide will also be available for distribution 

during FY 1991. This document outlines basic approaches for developing biological criteria in all surface waters (streams, rivers, lakes, wetlands, 

estuaries). The primary focus of the document is to 

provide a reference guide to scientific literature that 

describes approaches and methods used to determine biological integrity of specific surface water 

types. 

Over the next triennium more detailed guidance 

will be produced that focuses on each surface water 

type (e.g., technical guidance for streams will be 

produced during FY 91). Comparisons of different 

biosurvey approaches will be included for accuracy, 

efficacy, and cost effectiveness. 

Appendix A: Common Questions and Their Answenr 

47 

Appendix B - - --

Biological Criteria Technical 

Reference Guide 

Table of Contents (tentative) 

SECTION 1. INTRODUCTION 

CJ Purpose of the Technical Support Document 

CJ Organization of the Support Document 

SECTION 2. CONCEPTUAL FRAMEWORK FOR BIOLOGICAL CRITERIA 

CJ Definitions 

CJ Biocriteria and the Scientific Method 

CJ Hypothesis Formulation and Testing 

CJ Predictions 

a Data Collection and Evaluation 

SECTION 3. QUALITY ASSURANCE/QUALITY CONTROL 

a Data Quality Objectives 

CJ Quality Assurance Program Plans and Project Plans 

CJ Importance of QNQC for Bioassessment 

CJ Training 

a Standard Procedures 

CJ Documentation 

CJ Calibration of Instruments 

SECTION 4. PROCESS FOR THE DEVELOPMENT OF BIOCRITERIA 

CJ Designated Uses 

CJ Reference Site or Condition 

CJ Biosurvey 

a Biological Criteria 

49 
Biological Criteria: National Program Guidance 

SECTION 5. BIOASSESSMENT STRATEGIES TO DETERMINE BIOLOGICAL INTEGRITY 

a Detailed Ecological Reconnaissance 

o Biosurveys of Targeted Community Segments 

o Rapid Bioassessment Protocols 

o Bioindlcators 

SECTION 6. ESTABLISHING THE REFERENCE CONDITION 

o Reference Conditions Based on Site-Specific Comparisons 

o Reference Conditions Based on Regions of Ecological Similarity 

o Reference Conditions Based on Habitat Assessment 

SECTION 7. THE REFERENCE CATALOG 

SECTION 8. THE INFLUENCE OF HABITAT ON BIOLOGICAL INTEGRITY 

o Habitat Assessment for Streams and Rivers 

o Habitat Assessment for Lakes and Reservoirs 

o Habitat Assessment for Estuaries and Near-Coastal Areas 

o Habitat Assessment for Wetlands 

SECTION 9. BIOSURVEY METHODS TO ASSESS BIOLOGICAL INTEGRITY 

o Biotic Assessment in Freshwater 

a Biotic Assessment in Estuaries and Near-Coastal Areas 

o Biotic Assessment in Wetlands 

SECTION 10. DATAANALYSIS 

o Sampling Strategy and Statistical Approaches 

o Diversity Indices 

o Biological Indices 

o Composite Community Indices 

APPENDIX A. Freshwater Environments 

APPENDIX B. Estuarine and Near-Coastal Environments 

APPENDIX C. Wetlands Environments 

APPENDIX D. Alphabetical Author/Reference Cross Number Index for the Reference Catalog 

APPENDIX E. Reference Catalog Entries 

LIST OF FIGURES 

a Figure 1 Bioassessment decision matrix 

o Figure 2 Specimen of a reference citation in the Reference Catalog 

50 
Appe11dix C 

Biological Criteria 

Development by States 

Table of Contents (tentative) 

I. Introduction 

II. Key Concepts 

Ill. Biological Criteria Across the 50 States 

IV. Case Study of Ohio 

v. 

A. Introduction 

1 . Derivation of Biological Criteria 

2. Application of Biological Criteria 

B. History 

1 . Development of Biological Criteria 

2. Current Status of Biological Criteria 

C. Discussion 

1. Program Resources 

2. Comparative Cost Calculations 

3. Program Evaluation 

Case Study of Maine 

A. Introduction 

1 . Derivation of Biological Criteria 

2. Application of Biological Criteria 

B. History 

· 1 . Development of Biological Criteria 

2. Program Rationale 

C. Discussion 

1 . Program Resources 

2. Program Evaluation 

VI. Case Study of North Carolina 

A. Introduction 

1. Derivation of Biological Criteria 

2. Application of Biological Criteria 

B. History 

1. Development of Biological Criteria 

2. Current Status of Biological Criteria 

C. Discussion 

1. Program Resources 

2. Program Evaluation 

VII. Case Study of Arkansas 

A. Introduction 

1. Derivation of Biological Criteria 

2. Application of Biological Criteria 

B. History 

1. Development of Biological Criteria 

2. Current Status of Biological Criteria 

C. Discussion 

1. Program Resources 

2. Program Evaluation 

VIII. Case Study of Florlda 

A. Introduction 

1. Derivation of Biological Criteria 

2. Application of Biological Criteria 

B. History 

C. Discussion 

IX. Case Summaries of Six States 

A. Connecticut 

B. Delaware 

C. Minnesota 

D. Nebraska 

E. NewYork 

F. Vermont 

51 

Appendix D 

Contributors and Reviewers 

Contributors 

Gerald Ankley 

USEPA Environmental Research 

Lab 

6201 Congdon Blvd. 

Duluth, MN 55804 

John Arthur 

US EPA 

ERL-Duluth 

6201 Congdon Blvd. 

Duluth, MN 55804 

Patricia Balley 

Division of Water Quality 

Minnesota Pollution Control Agency 

520 Lafayette Road 

St Paul, MN 55155 

Joe Ball 

Wisconsin DNR 

Water Resource Management 

(WR/2) 

P.O. Box 7291 

Madison, WI 53707 

Mlchael Barbour 

EA Engineering, Science, and 

Technology Inc. 

Hunt Valley/Loveton Center 

15 Loveton Circle 

Sparks, MD 21152 

Raymond Beaumier 

Ohio EPA 

Water Quality Laboratory 

1030 King Avenue 

Columbus, OH 43212 

John Bender 

Nebraska Department of 

Environmental Control 

P.O. Box 948n 

State House Station 

Lincoln, NE 69509 

Mark Blosser 

Delaware Department of Natural 

Resources - Water Quality Mgmt. 

Branch 

P.O. Box 1401, 89 Kings Way 

Dover, DE 19903 

Robert Bode 

New York State Department of 

Environmental Conservation 

Box 1397 

Albany, NY 12201 

Lee Bridges 

Indiana Department of Environment 

Management 

5500 W. Bradbury 

Indianapolis, IN 46241 

Clalre Buchanan 

Interstate Commission on Potomac 

River Basin 

611 O Executive Boulevard Suite 300 

Rockville, MD 20852-3903 

David Courtemanch 

Maine Department of 

Environmental Protection 

Director, Division of Environmental 

Evaluation and Lake Studies 

State House No. 17 

Augusta, ME 04333 

53 

Norm Crisp 

Environmental Services Division 

USEPA Region 7 

25 Funston Road 

Kansas City, KS 66115 

Susan Davies 

Maine Department of 

Environmental Protection 

State House No. 17 

Augusta, ME 04333 

Wayne Davis 

Environmental Scientist 

Ambient Monitoring Section 

USEPA Region 5 

536 S. Clark St. (5-SMQA) 

Chicago, IL 60605 

Kenneth Duke 

Batte lie 

505 King Avenue 

Columbus, OH 43201-2693 

Gary Fandrel 

Minnesota Pollution Control Agency 

Division of Water Quality 

520 La Fayette Road North 

St. Paul, MN 55155 

Steve Fiske 

Vermont Department of 

Environmental Conservation 

6 Baldwin St 

Montpelier, VT 05602 
Biological Criteria: National Program Guidance 

John Giese 

Arkansas Department Of Pollution 

Control and Ecology 

P.O. Box 9583 

8001 National Drive 

Little Rock, AR 72209 

Steven Glomb 

Office of Marine and Estuarine 

Protection 

USEPA (WH-556F) 

401 M Street SW 

Washington, DC 20460 

Steve Goodbred 

Division of Ecological Services 

U. S. Fish and Wildlife Service 

1825 B. Virginia Street 

Annapolis, MD 21401 

Jim Harrison 

USEPA Region 4 

345 Courtland St. (4WM-MEB) 

Atlanta, GA 30365 

Margarete Heber 

Office of Water Enforcements and 

Permits 

USEPA (EN-336) 

401 M Street SW 

Washington, DC 20460 

Steve Hedtke 

US EPA Environmental Research 

Lab 

6201 Congdon Blvd. 

Duluth, MN 55804 

Robert Hite 

Illinois EPA 

2209 West Main 

Marion, IL 62959 

Linda Holst 

USEPA Region 3 

841 Chestnut Street 

Philadelphia, PA 19107 

Evan Hornig 

USEPA Region 6 

First Interstate Bank at Fountain 

Place 

1445 Ross Avenue, Suite 1200 

Dallas, TX 75202 

William .B. Homing II 

Aquatic Biologist, Project 

Management Branch 

USEPNORD Env. Monitoring 

Systems 

3411 Church St. 

Cincinnati, OH 45244 

Robert Hughes 

NSI Technology Services 

200 SW 35th Street 

Corvallis, OR 97333 

Jim Hulbert 

Florida Department of 

Environmental Regulation 

· Suite232 

3319 Maguire Blvd. 

Orlando, FL 32803 

James Kennedy 

Institute of Applied Sciences 

North Texas State University 

Denton, TX 76203 

Richard l,angdon 

Vermont Department of 

Environmental 

Conservation--10 North 

103 S. Main Street 

Waterbury, VT 05676 

John Lyons 

Special Projects Leader 

Wisconsin Fish Research Section 

Wisconsin Department of Natural 

Resources 

3911 Fish Hatchery Rd. 

Fitchburg, WI 53711 

Anthony Maclorowskl 

Batte lie 

505 King Avenue 

Columbus, OH 43201-2693 

Suzanne Marcy 

Office of Water Regulations and 

Standards 

USEPA (WH 585) 

401 M St. SW 

Washington, DC 20460 

Scott Mattee 

Geological Survey of Alabama 

PO DrawerO 

Tuscaloosa, AL 35486 

54 

John Maxted 

Delaware Department of Natural 

Rese>urces and Enviro.,mental 

Control 

39 Kings Highway, P.O. Elox 1401 

Dover, DE 19903 

Jimmie Overton 

NC De,:>t of Natural Resoa.irces and 

Commu nlty Developmenl 

P.O. Bolt< 27687 

512 N. Salisbury 

Raleigh'"' NC 27611-7687 

Steve P aulsen 

Envirornental Research Center 

University of Nevada-Las Vegas 

4505 Maryland Parkey 

Las Veg as, NV 89154 

Loys P•rrlsh 

USEPA -Region 8 

P.O. Bo>< 25366 

Denver Federal Center 

Denver, CO 80225 

David Penrose 

Environmental Biologist 

North Carolina Departme.,t of 

Natural Resources anal 

Commu.,ity Developrmnt 

512 N. Salisbury Street 

Raleighr NC 27611 

Don PhelP.S 

USE PA 

Environmental Research Lab 

South Ferry Road 

Narraga nsett, RI 02882 

Ernest Pizzuto 

Connecf:icut Department 

Environmental Protect! on 

122 Was.hington Street 

Hartford ~ CT 06115 

James P'lafkln 

Office of Water Regulations and 

Stanclards 

USEPA (WH 553) 

401 M S-treet, SW 

Washin~ton, DC 20460 

Ronald Freston 

Biological Science Coordi nator 

USEPA Region 3 

Wheeling Office (3ES12) 

303 Methodist Building 

Wheeling, WV 26003 
Ronald Raschke 

Ecological Support Branch 

Environmental Services Division 

USEPA Region 4 

Athens, GA 30613 

Mark Southerland 

Dynamac Corporation 

The Dynamac Building 

11140 Rickville Pike 

Rockville, MD 20852 

James Thomas 

Newfound Harbor Marine Institute 

Rt. 3, Box 170 

Big Pine Key, FL 33043 

Nelson Thomas 

USEPA, ERL-Duluth 

Senior Advisor for National Program 

6201 Congdon Blvd. 

Duluth, MN 55804 

Reviewers 

PaulAdamus 

Wetlands Program 

NSI Technology Services 

200 S.W. 35th Street 

Corvallis, OR 97333 

Rick Albright 

USEPA Region 10 (WD-139) 

1200 6th Avenue NW 

Seattle, WA 98101 

Max Anderson 

USEPA Region 5 

536 S. Clark St. (5SCRL) 

Chicago, IL 60605 

Michael D. Bilger 

USEPA Region 1 

John F. Kennedy Building 

Boston, MA 02203 

Susan Boldt 

University of Wisconsin Extension 

Madison, WI 

Paul Campanella 

Office of Policy, Planning and 

Evaluation 

USEPA (PM 222-A) 

401 M St. S.W. 

Washington, DC 20460 

Randall Waite 

USEPA Region 3 

Program Support Branch (3WMIO) 

841 Chesnut Bldg. 

Philadelphia, PA 19107 

John Wegrzyn 

Manager, Water Quality Standards 

Unit 

Arizona Department of 

Environmental Quality 

2005 North Central Avenue 

Phoenix, AZ. 95004 

Thom Whittler 

NSI Technology Services 

200 SW 35th Street 

Corvallis, OR 97333 

Biii Wuerthele 

Water Management Division 

USEPA Region 8 (WM-SP) 

999 18th Street Suite 500 

Denver, CO 80202 

Cindy Carusone 

New York Department of 

Environmental Conservation 

Box 1397 

Albany, NY 12201 

Brian Choy 

Hawaii Department of Health 

645 Halekauwila St. 

Honolulu, HI 96813 

Biii Creal 

Michigan DNR 

Surface Water Quality Division 

P.O. Box 30028 

Lansing, Ml 48909 

Phll Crocker 

Water Quality Management Branch 

USE PA Region 6 I 1445 .Ross Ave. 

Dallas, TX 75202-2733 

Kenneth Cummins 

Appalachian Environmental Lab 

University of Maryland 

Frostburg, MD 21532 

Jeff DeShon 

Ohio EPA. Surface Water Section 

1030 King Ave. 

Columbus, OH 43212 

SS 

Appendix D: Contributors and Reviewers 

Chris Yoder 

Asst. Manager, Surface Water 

Section 

Water Quality Monitoring and 

Assessment 

Ohio EPA-Water Quality Lab 

1030 King Ave. 

Columbus, OH 43212 

David Yount 

US EPA Environmental Research 

Lab 

6201 Congdon Blvd. 

Duluth, MN 55804 

Lee Zeni 

Interstate Commission on Potomac 

River Basin 

611 O Executive Boulevard Suite 300 

Rockville, MD 20852-3903 

Peter Farrington 

Biomonitoring Assessments Officer 

Water Quality Branch 

Inland Waters Directorate 

Environment Canada 

Ottawa, Ontario K1 A OH3 

Kenneth Fenner 

USEPA Region 5 

Water Quality Branch 

230 S. Dearborn 

Chicago, IL 60604 

Jack Freda 

Ohio EPA 

Surface Water Section 

1030 King Avenue 

Columbus, OH 43212 

Toby Frevert 

Illinois EPA 

Division of Water Pollution Control 

2200 Churchill Road 

Springfield, IL 62706 

Cynthia Fuller 

USEPAGLNPO 

230 S. Dearborn 

Chicago, IL 60604 
Biological Criteria: National Program Guidance 

JeffGagler 

USEPA Region 5 

230 S. Dearborn (5WQS) 

Chicago, IL 60604 

Mary Jo Garrels 

Maryland Department of the 

Environment 

2500 Broening Highway 

Buildlng30 

Baltimore, MD 21224 

Jim Glattlna 

USEPA Region 5 

230 S. Dearborn (5WQP) 

Chicago, IL 60604 

Jim Green 

Environmental Services Division 

USEPA Region 3 

303 Methodist Bldg. 

11th and Chapllne 

Wheeling, WV 26003 

Larlndo Gronner 

USEPA Region 4 

345 Courtland St. 

Atlanta, GA 30365 

Martin Gurtz 

U.S. Geological Survey, WAD 

P.O. Box 2857 

Raleigh, NC 27602-2857 

Rick Hafele 

Oregon Department Environmental 

Quality 

1712 S.W. 11th Street 

Portland, OR 97201 

Steve Helskary 

MN Pollution Control Agency 

520 Lafayette Road 

Sl Paul, MN 55155 

Rollie Hemmett 

USEPA Region 2 

Environmental Services 

Woodridge Avenue 

Edison, NJ 08837 

Charles Hocutt 

Horn Point Environmental 

Laboratory 

Box 775 University of Maryland 

Cambridge, MD 21613 

Hoke Howard 

USEPA Region 4 

College Station Road 

Athens, GA 30605 

Peter Husby 

USEPA Region 9 

215 Freemont St 

San Fr'ancisco, CA 94105 

Gerald Jacobi 

Environmental Sciences 

School of Science and Technology 

New Mexico Highlands University 

Las Vegas, NM 87701 

James Karr 

Department of Biology 

Virginia Polytechnic Institute and 

State University 

Blacksburg, VA 24061-0406 

Roy Kleinsasser 

Texas Parks and Wildlife 

P.O. Box947 

San Marcos, TX 78667 

Don Klemm 

USEPA Environmental Monitoring 

and Systems Laboratory 

Cincinnati, OH 45268 

Robin Knox 

Louisiana Department of 

Environment Quality 

P.O. Box 44091 

Baton Rouge, LA 70726 

Robert Koroncal 

Water Management Division 

USEPA Region 3 

847 Chestnut Bldg. 

Philadelphia, PA 19107 

Jim Kurztenbach 

USEPA Region 2 

Woodbridge Ave. 

Rariton Depot Bldg. 10 

Edison, NJ 08837 

Roy Kwiatkowski 

Water Quality Objectives Division 

Water Quality Branch 

Environment Canada 

Ottawa, Ontario Canada 

K1AOH3 

56 

Jim LaJorchak 

EMSL-Cincimati 

U.S. Enavironmental Protection 

Agency 

Cincinr.ati, OH 

David Lenat 

NC Dept of Natural Reso ureas and 

Community Developrnen1 

512 N. ~alisbury St. 

Raleigt., NC 27611 

James Luey 

USEPA Region 5 

230 S. Dearborn (5WOS)t 

Chicago, IL 60604 

Terryfaaret 

Nebrasl-<a Department of 

Envir onmental Control 

Box 948177 

State He>use Station 

Lincoln, NE 69509 

Wally Mlatsunaga 

Illinois EPA 

1701 First Ave., #600 

Maywood, IL60153 

Robert Mosher 

Illinois EPA 

2200 Churchill Rd. #15 

P.O. Bo)!( 19276 

SpringfiEld, IL 62794 

Phllllp Oshlda 

USEPA Region 9 

215 Fre.-nont Street 

San Francisco, CA 9410S. 

Biil Painter 

USEPA, OPPE 

401 M S<treet, SW (W43513) 

WashinQton, DC 20460 

Rob Pepin 

USEPA ;Region 5 

230 S. Dearborn 

Chicage>, IL 60604 

Wayne Foppe 

Tenness-ee Valley Authority 

270 Haruy Bldg. 

Chattanooga, TN 37401 

Walter Pledmon 

USEPA l:tegion 5 

230 S. Dearborn 

Chicago , IL 60604 
Landon Rosa 

Florida Department of 

Environmental Regulation 

2600 Blair Stone Road 

Tallahassee, FL 32399 

Jean Roberts 

Arizona Department of 

Environmental Quality 

2655 East Magnolia 

Phoenix, AZ. 85034 

Charles Saylor 

Tennessee Valley Authority 

Field Operations Eastern Area 

Division of Services and Field 

Operations 

Norris, TN 37828 

Robert Schacht 

Illinois EPA 

1701 First Avenue 

Maywood, IL60153 

Duane Schuettpelz 

Chief, Surface Water Standards and 

Monitoring Section-Wisconsin 

Department of Natural 

Resources 

Box 7921 

Madison, WI 53707 

Bruce Shackleford 

Arkansas Department of Pollution 

Control and Ecology 

8001 National Drive 

Little Rock, AR 72209 

Larry Shepard 

USEPA Region 5 

230 S. Dearborn (5WQP) 

Chicago, IL 60604 

Jerry Shulte 

Ohio River Sanitation Commission 

49 E. 4th St., Suite 851 

Cincinnati, OH 45202 

Thomas Simon 

USEPA Region 5 

536 S. Clark St. (5SCRL) 

Chicago, IL 60605 

J. Singh 

USEPA Region 5 

536 Clark St. (5SCDO) 

Chicago, IL60605 

57 

Appendix O: Contributors and RevlBWers 

Marc Smith 

Biomonltoring Section 

Ohio EPA 

1030 King Avenue 

Columbus, OH 43212 

Denise Steurer 

USEPA Region 5 

230 S. Dearborn 

Chicago, IL S0604 

Wiiiiam Tucker 

Supervisor, Water Quality 

Monitoring 

Illinois EPA 

Division of Water Pollution Control 

4500 S. Sixth Street 

Springfield, IL 62706 

Stephen Twidwell 

Texas Water Commission 

P.O. Box 13087 

Capital Station 

Austin, TX 78711-3087 

Barbara Wiiiiams 

USEPA Region 5 

230 S. Dearborn 

Chicago, IL 60604